sys7.1-doc-wip/Drivers/IOP/SCCIOP.aii
2019-07-27 22:37:48 +08:00

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;
; File: SCCIOP.aii
;
; Contains: xxx put contents here (or delete the whole line) xxx
;
; Written by: xxx put name of writer here (or delete the whole line) xxx
;
; Copyright: © 1988-1990 by Apple Computer, Inc., all rights reserved.
;
; Change History (most recent first):
;
; <3> 1/18/90 SWC WTO/Fix bugs in InstallTask and KillTask.
; <1.4> 12/8/89 WTO Fixed bug in version message to kernel. Range check on Driver ID
; was returning error. Needed to add compare to $00.
; <1.3> 7/8/89 CCH Added EASE comments to file.
; <1.2> 6/27/89 BTO Needed for AURORA padding
; <•1.1> 2/8/89 SGS Initial release
; <1.0> 11/9/88 CCH Adding to EASE.
;
; To Do:
;
*
* File SCCIop.aii
*
* Copyright 1988 (c) Apple Computer Inc.
*
* Main routines to handle IOP. The Kernel is downloaded into the IOP
* during the IOPMgr initialization process. The IOPMgr then reads
* PRAM to set the ByPass mode to the appropriate state.
*
* Written by Bill O'Connor 2/19/88
* with ideas and code from Ron Hocksprung
* Gary Davidian
*
* Edit History
*
*^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
Machine M65CX02
Longa off
Longi off
blanks on
print nopage, nomdir
include 'SCCIOPSysEqu.aii' ; IOP Sytem includes
include 'SCCIOPEqu.aii' ; IOP Kernel includes
Seg 'IOPOS'
*^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
*
* Vectored interrupt table
*
*^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
Seg 'Vectors'
*^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
*
* Interrupt vector address table.
*
*^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
Vect Proc
Import NonMaskable, \
Reset, \
IRQ :Code
DC.W NonMaskable
DC.W Reset
DC.W IRQ
endproc
*^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
*
* Main entry into PIC kernel
*
*^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
Seg 'Main'
Export NonMaskable, \
Reset, \
IRQ
*^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
*
* NonMaskable interrupt handler.
*
*^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
NonMaskable Proc
Lda #NonMask ; Let us know we are in NonMaskable Loop
Bra NonMaskable ; Should never get one
endproc
*^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
*
* IRQ - save registers and jsr to ISR dispatcher.
*
*^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
IRQ Proc
Import ISR_Dsptch : Code
Pha ; Save registers.
Phy
Phx
Jsr ISR_Dsptch ; Interrupt handler
Plx ; Restore registers
Ply
Pla
Rti
endproc
*^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
*
* Reset handler.
*
*^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
Reset Proc
Import Cmd_Table, \
VerInfo : Data
Import Kern_Task, \
Cmd_JmpTable, \
RxMsg_Signal, \
SCC_Dsptch, \
Timer_ISR, \
Init_Timer, \
Msg_Scan : Code
Sei ; Interrupts off
Stz Int_Host
Lda #SCC_Port|ByPass_Bit|PClk39
Sta SCC_Cntl ; Initialize SCC control reg
Lda #IO_Cntl_init ; Get initial value
Sta IO_Cntl ; Initialize I/O control reg
Lda #Host_Msk ; Enable host interrupts
Sta Int_Mask
Lda SCC_ACntl ; Sync SCC for writes
*
* Clear page zero
*
Ldx #$00 ; Index
@ClearLoop
Stz $00,x ; Zero out a byte
Dex ; Point to next byte
Bne @ClearLoop ; Clear the entire zero page
Stz DMA1_Cntl ; Init DMA1
Stz DMA2_Cntl ; Init DMA2
Stz TD_Cntl ; Init Timer DPLL control
Stz Int_Host ; Init host interrupt register
*
* Transfer the kernel command addresses to the zero page table
*
Ldx #KCmd_Table_size ; Begin transfer of command table
@Loop Lda Cmd_Table,x
Sta Krn_CmdBase,x
Dex
Bpl @Loop
*
* Initialize Zero Page variables
*
*
* IMPORTANT !!!!!
*
* Because of the manor in which the 6502 does a rts the address
* used must be the actual address minus 1
*
DvrA_Addr Set DvrA_Base-1
DvrB_Addr Set DvrB_Base-1
Lda #DvrA_ID ; Initialize the driver task ID table
Sta Dvr_TaskID
Lda #DvrB_ID
Sta Dvr_TaskID+1
Lda #>DvrA_Addr ; Install the Initialization vector for driver A
Sta Init_Vec+1
Lda #<DvrA_Addr
Sta Init_Vec
Lda #>DvrB_Addr ; Install the Initialization vector for driver B
Sta Init_Vec+3
Lda #<DvrB_Addr
Sta Init_Vec+2
Lda #>DvrA_Close ; Install the Close vector for driver A
Sta Close_Vec+1
Lda #<DvrA_Close
Sta Close_Vec
Lda #>DvrB_Close ; Install the Close vector for driver B
Sta Close_Vec+3
Lda #<DvrB_Close
Sta Close_Vec+2
Lda #$ff
Sta Bypass_Flag ; Set ByPass_Flag to on.
Jsr Init_Timer
_Reg_Ver Kern, VerInfo
_Inst_ISR HOST, Msg_Scan ; Install message scan for host interrupt
_Inst_ISR SCC, SCC_Dsptch ; Install the SCC interrupt dispatcher
_Inst_ISR TIMER, Timer_ISR
_Inst_RxMsgSgn 1, RxMsg_Signal ; Install the kernel receive message signaller
Lda #MaxRxMsg
Sta RxMsgCnt ; PIC Kernel uses 7 messages
Sta TxMsgCnt ; Both in and out
Ldx #$ff ; Stack base is $01FF
Stx Int_Reg ; Clear the interrupt register
Stx IOPAlive ; Tell IOPMgr we are Alive
Txs ; Initialize stack
Jmp Kern_Task ; Interrupts will be cleared when
; Event Wait is called.
endproc
*^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
*
* ISR_Dsptch - determine interrupt source and dispatch to ISR.
*
*^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
ISR_Dsptch Proc
Import ISR_table, \
ISR_Decode :Data
Ldx Int_reg ; Get the interrupt latch
Lda ISR_Decode,x
Tax
Jmp (ISR_table,x) ; Dispatch the interrupt
endproc
*^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
*
* SCC_Dsptch - determine source and dispatch SCC interrupts.
*
*^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
SCC_Dsptch Proc
Import SCC_table, \
UnKnown_Int :Code
Lda #Rd_Reg2 ; Read the SCC interrupt latch
Sta SCC_BCntl ; Interrupt latch is register 2 port B
Ldx SCC_BStat ; Read the status V1 V2 V3
Jmp (SCC_table,x) ; Dispatch the interrupt
endproc
*^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
*
* Unknown_SCCInt - unknown SCC interrupt handler.
*
* This routine handles interrupts that occur but do
* not have an SCCISR installed.
*
*^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
UnKnown_SCCInt Proc
Brk
endproc
*^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
*
* Unknown_Int - unknown interrupt handler.
*
* This routine handles interrupts that occur but do
* not have an ISR installed.
*
*^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
Unknown_Int Proc
Tsx ; Get the stack pointer
Lda StackPage+6,x ; Get the psw from the stack
Bit #pswB ; Was it a break that caused the interrupt
Bne BRK_Handler ; Yes
Rts ; No, just return
*^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
*
* BRK_Handler - handle a software interrupt
*
*^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
BRK_Handler Tsx ; Get the stack pointer
*
* Cycle through stack so that we can see it on the logic analyzer
*
Do_Again Inx
Beq BRK_Handler
Lda StackPage,x
Bra Do_Again
endproc
*^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
* Entry Points
*
* Rel_Task - release a task for one task cycle.
*
* Ev_Wait - wait for an event to happen.
*
* The return address should already be on the stack.
* Ev_Wait falls through into Ev_Dsptch.
*
* Register A - event mask.
*
* On exit register A contains the tEvent for the Task.
*
*^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
Rel_Task Proc
Export Ev_Wait
Import tSp, \
tNext, \
tEvent, \
tWait : Data
Lda #$80 ; This event is always set
; therefore the task will execute the
; next task cylce
Ev_Wait Ldy Cur_Task ; Get the Task ID
Sta tWait,y ; Store the event mask
*
* Ev_Dsptch - entry to task dispatcher.
*
Sei
Ldy Cur_Task ; Get the current task ID
Tsx
Txa
Sta tSp,y ; Save the task's stack pointer
Cli
Ldx #$FF
@Scan Lda tNext,y ; Get the next task ID
Tay
Lda tEvent,y ; Check the flags to see if this one is ready
And tWait,y
Stx IOPAlive ; This lets the Host know we're still alive
Beq @Scan
Sei
Sty Cur_Task ; Switch Tasks
Ldx tSp,y ; Get this task's stack pointer
Txs
Cli
Rts ; go to the task
endproc
*^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
*
* Ev_Signal - signal a task that an event has occurred.
*
* Events are flagged by setting bits in the tEvent byte of the
* TCB of the task to receive the signal.
*
* Register X - ID of task to signal.
* Register A - event flag.
*
*^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
Ev_Signal Proc
Import tEvent : Data
Php
Sei
Ora tEvent,x ; Set the event bit
Sta tEvent,x ; Save it in the task's TCB
Plp
Rts
endproc
*^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
*
* Ev_Reset - reset an event flag.
*
* Register A - complement of event flag.
*
*^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
Ev_Reset Proc
Import tEvent : Data
Php
Sei
Ldx Cur_task ; We can only reset our own task
And tEvent,x ; Reset the event bit
Sta tEvent,x ; Save it in the task's TCB
Plp
Rts
endproc
*^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
*
* Msg_Scan - handle interrupts from host CPU. Must be installed
* when processor is reset.
*
* Scan messages for New Message Sent and Message Complete. Each
* task installs message handlers that signal the task when new messages
* are received or messages are completed. Each task must install a
* handler for each message box it intends to use.
*
* The only message the kernel will accept when in ByPassMode
* is ByPassMode(Off).
*
*
*^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
Msg_Scan Proc
Import TxMsgSignal, \
RxMsgSignal : Code
Import MsgNumTimes2 : Data
Lda #Host_Msk
Sta Int_Reg ; Clear the host interrupt
Trb Int_Mask ; Disable host interrupts
Cli ; Renable interrupts of higher priority
Lda ByPass_Flag ; We don't do anything in bypass mode
Bne Do_ByPass ; except receive on message one
*
* Service Completed Transmit Messages first
*
Ldy TxMsgCnt ; Get highest Tx message number
Lda #MsgCmplt ; Get the desired message state
@TxMsgLoop Cpa TxMsgState,y ; See if the message completed
Bne @TxMsgNext ; If no service needed goto next msg
Phy ; Preserve loop counter
Ldx MsgNumTimes2,y ; Convert message number to table index
Jsr TxHandler ; Call the handler
Ply ; Restore the message number
Lda #Idle
Sta TxMsgState,y ; Change message state to Idle
Lda #MsgCmplt ; Restore desired message state
@TxMsgNext Dey ; Point to previous message
Bne @TxMsgLoop ; Loop through all messages
Bra RxMsgStart
*
* Service Receive New Message Sent last
*
Do_ByPass Ldy #1 ; In ByPass mode we only receive message 1
Bra ByPassSkip ; for the kernel
RxMsgStart Ldy RxMsgCnt ; Get highest Rx message number
ByPassSkip Lda #NewMsgSent ; Get the desired message state
@RxMsgLoop Cpa RxMsgState,y ; See if message just arrived
Bne @RxMsgNext ; If no service needed
Lda #MsgRcv
Sta RxMsgState,y ; Change message state to Message Received
Phy ; Preserve loop counter
Ldx MsgNumTimes2,y ; Convert message number to table index
Jsr RxHandler ; Call the handler
Ply ; Restore the message number
Lda #NewMsgSent ; Restore desired message state
@RxMsgNext Dey ; Point to previous message
Bne @RxMsgLoop ; Loop through all messages
Sei
Lda #Host_Msk ; Get the host interrupt bit
Tsb Int_Mask ; Re-enable host interrupts
Rts ; All done
TxHandler Jmp (TxMsgSignal-2,x) ; Go to handler - msg's start at 1
RxHandler Jmp (RxMsgSignal-2,x) ; Go to handler - msg's start at 1
endproc
*^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
*
* RxMsg_Signal - signal kernel that a message has arrived.
*
*^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
RxMsg_Signal Proc
Import Cmd_JmpTable : Code
Ldx #Kern_ID ; ID of task we wish to signal
Lda #RxMsg ; Signal we want to send
Jmp Cmd_JmpTable+(SignalTask*3) ; Signal Task Command has an RTS
endproc
*^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
*
* Kern_Task - main kernel task routine and event dispatcher
*
*^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
Kern_Task Proc
Import Dsptch_KRxMsg : Code
Import Cmd_JmpTable : Code
_Wait_Event RxMsg ; Wait until we get a receive message event
Asl A ; tEvent is already in register A
Tax
Jmp (Kern_Disp-2,x)
Kern_Disp DC.W Dsptch_KRxMsg ; Dispatch Kernel message is the only
; event we look for.
endproc
*^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
*
* Dsptch_KRxMsg - Decode and dispatch messages to Kernel
*
*
*^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
Dsptch_KRxMsg Proc
Import MsgNumTimes32 : Data
Import Kern_Task, \
Alloc_Driver, \
DeAlloc_Driver, \
ByPass_Mode, \
Init_Driver, \
Version, \
SCC_Control, \
Cmd_JmpTable : Code
_Reset_Event RxMsg ; Reset the event
Ldy #$01 ; Kernel has only one message (msg1)
Ldx MsgNumTimes32,y ; Get the Receive message page offset
Lda ByPass_Flag ; Check for ByPass mode
Bne Do_ByPass
Procede Lda RxMsgPage,x ; Get the command byte
Beq UnKnown_Msg ; Zero is not a command
Cmp #Max_KMsg+1 ; If > the max msg #
Bge Unknown_Msg ; branch to unknown message routine
Stz RxMsgPage,x ; Clear the message byte
Asl A ; Make it a word offset
Phx
Tax
Jmp (Msg_Table-2,x) ; Dispatch the command
Do_ByPass Lda RxMsgPage,x
Cmp #ByPass ; Is it a ByPass Call
Beq Procede ; Yes, procede
Cmp #SCCCntl ; Allow the SCC Control register call.
Beq Procede ; Yes, procede with message
Stz RxMsgPage+2,x
Lda ByPass_Flag
Sta RxMsgPage+1,x ; Return ByPass client ID
Lda #InByPass
Bra Complete
UnKnown_Msg Stz RxMsgPage+2,x
Stz RxMsgPage+1,x
Lda #UnKnwnMsg ;
Complete Sta RxMsgPage,x ; Return the error
Lda #MsgCmplt ; Tell host we've completed the message
Sta RxMsgState,y ; Store it in the message state variable
Lda #Int0 ; Load A with host interrupt bit
Tsb Int_Host
Jmp Kern_Task ; Return to wait for next event
Msg_Table DC.W Alloc_Driver
DC.W DeAlloc_Driver
DC.W Init_Driver
DC.W ByPass_Mode
DC.W Version
DC.W SCC_Control
endproc
*^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
*
* Alloc_Driver
*
* Passed
*
* struct AllocMsgType {
* byte msgNum; /* Alloc_Channel msg = $01 */
* byte Driver; /* Dvr A = $00 Dvr B = $01 */
* byte ClientID; /* Port use ID > $00 */
* }
*
* Returns
*
* struct AllocErrType{
* byte errNum; /* NoErr = $00
* Error = -1
* DvrInUse = -4
* InBypass = -5
* */
* byte ClientID; /* ID > 0 if port in use */
* int Addr; /* Driver load address - 1 */
* }
*
* Stack Info
* -----------------
* | Msg # * 32 |
* -----------------
* SP ->
*
* Register Y - contains message number starting at 1
*
*^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
Alloc_Driver Proc
Import Kern_Task : Code
Plx ; Restore X - msg number * 32
Phy
Ldy RxMsgPage+1,x ; Get the channel byte (DvrA or DvrB)
Cpy #MaxDvr+1 ; Are we trying to open a nonexistant driver
Bge ERR
Cpy #DvrA
Blt ERR
Stz RxMsgPage+1,x ; Clear the Driver byte
Lda Dvr_Use,y ; See if the driver is in use
Bne InUse
Lda RxMsgPage+2,x ; Get the ClientID byte
Sta Dvr_Use,y ; Store the ID if the driver is free
Stz RxMsgPage+2,x ; Clear the ClientID
Tya ; Make the driver ID a word offset
Asl A
Tay
Lda Init_Vec,y ; Return the driver starting address
Sta RxMsgPage+3,x
Lda Init_Vec+1,y
Sta RxMsgPage+2,x
Bra Complete ; NoErr is reported because we've been
; clearing bytes as we go!!!
InUse Stz RxMsgPage+2,x ; Clear the ClientID of the message
Sta RxMsgPage+1,x ; Return the ClientID of the client using the Driver
Lda #DvrInUse
Sta RxMsgPage,x ; Return the error Driver In Use
Bra Complete
ERR Stz RxMsgPage+2,x ; Clear ClinetID
Stz RxMsgPage+1,x ; Clear driver byte
Lda #Error ; We made a boo boo
Sta RxMsgPage,x ; Return the code
Complete Ply
Lda #MsgCmplt ; Tell host we've completed the message
Sta RxMsgState,y ; Store it in the message state variable
Lda #Int0 ; Load A with host interrupt bit
Tsb Int_Host
Jmp Kern_Task ; Return to wait for next event
endproc
*^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
*
* DeAlloc_Driver
*
* Passed
*
* struct DeAllocMsgType {
* byte msgNum; /* DeAlloc_Channel msg = $02 */
* byte Driver; /* Dvr A = $00 Dvr B = $01 */
* }
*
* Returns
*
* struct DeAllocErrType{
* byte errNum; /* NoErr = $00
* Error = -1
* InByPass = -5
* */
* }
*
* Stack Info
* -----------------
* | Msg # * 32 |
* -----------------
* SP ->
*
* Register Y - contains message number starting at 1
*
*^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
DeAlloc_Driver Proc
Import Kern_Task : Code
Plx ; Restore X - msg number * 32
Phy
Ldy RxMsgPage+1,x ; Get the driver byte (DvrA or DvrB)
Cpy #MaxDvr+1 ; Are we trying to close a nonexistant driver
Bge ERR
Cpy #DvrA
Blt ERR
Stz RxMsgPage+1,x ; clear the channel byte
Lda #00
Sta Dvr_Use,y ; Disable driver use byte
Tya
Asl A ; Make the channel number a word offset
Tax
Jsr FakeIndirX
Bra Complete
ERR Lda #Error ; Report that we made a boo boo
Sta RxMsgPage,x ; We were trying to close a nonexistant Driver
Complete Ply
Lda #MsgCmplt ; Tell host we've completed the message
Sta RxMsgState,y ; Store it in the message state variable
Lda #Int0 ; Load A with host interrupt bit
Tsb Int_Host
Jmp Kern_Task ; Return to wait for next event
FakeIndirX Jmp (Close_Vec,x) ; Jump to the channel's close routine
endproc
*^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
*
* Init_Driver
*
* Passed
*
* struct InitMsgType {
* byte msgNum; /* Init_Channel msg = $03 */
* byte Driver; /* Dvr A = $00 Dvr B = $01 */
* }
*
* Returns
*
* struct InitErrType {
* byte errNum; /* NoErr = $00
* Error = -1
* InByPass = -5
* NotAlloc = -6
* */
* }
*
*
* On Entry
*
* Stack Info
* -----------------
* | Msg # * 32 |
* -----------------
* SP ->
*
* Register Y - contains message number starting at 1
*
* On Exit
*
*
*^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
Init_Driver Proc
Import Kern_Task, \
Cmd_JmpTable : Code
Plx ; Get the message offset
Phy ; Save the message number
Ldy RxMsgPage+1,x ; Get the driver byte (DvrA or DvrB)
Cpy #MaxDvr+1 ; Are we trying to init a nonexistant driver
Bge ERR
Cpy #DvrA
Blt ERR
Stz RxMsgPage+1,x ; Clear driver byte
Lda Dvr_Use,y ; Check to see if driver has been allocated
Beq Not_Open
Phx ; Save the message offset
Lda Dvr_TaskID,y ; Get the Task ID for this driver
Pha ; Save Task ID temp.
Tya ; Load A with the driver byte
Asl A ; Make the driver byte a word offset
Tax
Lda Init_Vec,x ; Get the address of the driver init routine
Ldy Init_Vec+1,x
Plx ; Get the task ID
Sec ; Set Carry for Install Task
Jsr Cmd_JmpTable+(InstTask*3) ; Install the task into the Q
_Wait_Event InitFin ; Wait for the task to signal it's completion
_Reset_Event InitFin ; Reset tWait so we don't get this event again
Plx ; Restore the message offset
Stz RxMsgPage,x ; Signal No Error
Bra Complete
Not_Open Lda #NotAlloc ; Not open, therefore cannot be initialized
Sta RxMsgPage,x
Bra Complete
ERR Lda #Error ; Report that we made a boo boo
Sta RxMsgPage,x ; We were trying to close a nonexistant driver
Complete Ply
Lda #MsgCmplt ; Tell host we've completed the message
Sta RxMsgState,y ; Store it in the message state variable
Lda #Int0 ; Load A with host interrupt bit
Tsb Int_Host
Jmp Kern_Task ; Return to wait for next event
endproc
*^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
*
* ByPass_Mode
*
* Passed
*
* struct ByPassMsgType {
* byte msgNum; /* ByPass_Mode msg = $04 */
* byte On_Off; /* Off = 0 On = 1 */
* byte ClientID; /* ID > 0 */
* }
*
* Returns
*
* struct ByPassErrType{
* byte errNum; /* NoErr = $00
* ChanInUse = -4
* InByPass = -5
* BadID = -7
* */
* Union {
* byte ByPassID; /* ID > 0 if in ByPass */
* byte ClientAID; /* ID > 0 If currently allocated */
* } switch;
* byte ClientBID; /* ID > 0 IF currently allocated */
* }
*
* Stack Info
* -----------------
* | Msg # * 32 |
* -----------------
* SP ->
*
*
* Register Y - contains message number starting at 1
*
*^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
ByPass_Mode Proc
Import Kern_Task, \
Cmd_JmpTable : Code
Plx
Phy
Ldy RxMsgPage+1,x ; Get the On/Off byte
Beq ByPass_Off ; = 0 means we want to turn ByPass Off
Stz RxMsgPage+1,x ; Clear On/Off byte
Lda Dvr_AUse ; Check to see if Driver A is closed
Bne In_Use
Lda Dvr_BUse ; Check to see if Driver B is closed
Bne In_Use
Lda ByPass_Flag ; Check to see if we are in ByPass Mode
Bne In_ByPass
Php
Sei
Phx
Jsr OnReset
Plx
Plp
Lda #ByPass_Bit|RTXCA_36|RTXCB_36 ; Put PIC into ByPass Mode, RTXC=3.6 MHZ
Tsb SCC_Cntl
Lda RxMsgPage+2,x ; Set ByPass_Flag to ID byte
Sta ByPass_Flag ;
Bra Complete
ByPass_Off Stz RxMsgPage+1,x ; Clear on off byte
Lda RxMsgPage+2,x ; Get the ID
Stz RxMsgPage+2,x ; Clear the ID
Cmp ByPass_Flag ; Make sure who ever put us in ByPass takes us out
Bne WrongID
Php
Sei
Lda #ByPass_Bit ; Take PIC out of ByPass Mode
Trb SCC_Cntl
Jsr OffReset
Plp
Stz ByPass_Flag ; Turn ByPass mode off
Bra Complete
WrongID Lda ByPass_Flag
Sta RxMsgPage+1,x ; Return the ID of the person who turned ByPass on
Lda #BadID ; Make sure who ever put us
Sta RxMsgPage,x ; in bypass mode takes us out!!!!
Bra Complete
In_ByPass Lda ByPass_Flag
Sta RxMsgPage+1,x ; Return the ID of the person who turned ByPass on
Stz RxMsgPage+2,x ; Clear ID
Lda #InByPass
Sta RxMsgPage,x ; Return the error In ByPass mode
Bra Complete
In_Use Lda Dvr_AUse
Sta RxMsgPage+1,x ; Return driver A ClientID
Lda Dvr_BUse
Sta RxMsgPage+2,x ; Return driver B ClientID
Lda #DvrInUse ; Report that a driver is in use
Sta RxMsgPage,x
Complete Ply
Lda #MsgCmplt ; Tell host we've completed the message
Sta RxMsgState,y ; Store it in the message state variable
Lda #Int0 ; Load A with host interrupt bit
Tsb Int_Host
Jmp Kern_Task ; Return to wait for next event
OffReset Lda #SCC_Msk
Tsb Int_Mask ; Enable SCC interrupts
Bra OffSkip
OnReset Lda #SCC_Msk
Trb Int_Mask
*
* Initialize the SCC
*
OffSkip Lda SCC_ACntl ; Synchronize Read/Writes
*
* Initialize the SCC
*
DoB Lda #Wr_reg9
Sta SCC_ACntl
Lda #ChanB_Reset
Sta SCC_ACntl
Ldx #0
@LoopB Lda Table,X ; Get the register number
Tay ; Transfer indicator bits
Iny ; Was it an $FF? (END OF TABLE?)
Beq DoA ; If so, exit
Sta SCC_BCntl ; Set register
Inx ; Move to next character
Lda Table,X ; Register contents
Sta SCC_BCntl
Inx
Bra @LoopB
DoA Lda #Wr_reg9
Sta SCC_ACntl
Lda #ChanA_Reset
Sta SCC_ACntl
Ldx #0
@LoopA Lda Table,X ; Get the register number
Tay ; Transfer indicator bits
Iny ; Was it an $FF? (END OF TABLE?)
Beq @Done ; If so, exit
Sta SCC_ACntl ; Set register
Inx ; Move to next character
Lda Table,X ; Register contents
Sta SCC_ACntl
Inx
Bra @LoopA
@Done Rts
Table
DC.B Wr_reg4, X16CLK|StopBit2
DC.B Wr_reg2, 00
DC.B Wr_reg3, Rx_8Bits
DC.B Wr_reg15, 00 ; Clear External status interrupts
DC.B Wr_reg0, Reset_ExtInt ; Reset external status interrupts twice ??
DC.B Wr_reg0, Reset_ExtInt
DC.B Wr_reg1, 00 ; Disable all interrupts
DC.B $ff ; End of table
endproc
*^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
*
* Version
*
* Passed
*
* struct VersionMsgType {
* byte msgNum; /* Version = $05 */
* byte DriverID; /* Driver A = $00 */
* /* Driver B = $01 */
* /* Kernel = $02 */
* }
*
* Returns
*
* struct VersionErrType{
* byte errNum; /* NoErr = $00 */
* ptr VerInfo; /* Pointer to version info */
* }
*
* Stack Info
* -----------------
* | Msg # * 32 |
* -----------------
* SP ->
*
*
* Register Y - contains message number starting at 1
*
*^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
Version Proc
Import VerInfo : Data
Import Kern_Task : Code
Plx
Phy
Lda RxMsgPage+1,x
Cmp #00 ; Do a range check on Driver ID
Blt Err
Cmp #Kern+1
Bge Err
Asl A
Tay
Lda Ver_Ptr,y ; Return the address of the version info
Sta RxMsgPage+1,x
Lda Ver_Ptr+1,y
Sta RxMsgPage+2,x
Cmplt Ply
Lda #MsgCmplt ; Tell host we've completed the message
Sta RxMsgState,y ; Store it in the message state variable
Lda #Int0 ; Load A with host interrupt bit
Tsb Int_Host
Jmp Kern_Task ; Return to wait for next event
Err Lda #Error ; Report Error and complete
Sta RxMsgPage,x
Bra Cmplt
endproc
*^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
*
* SCC_Control - turn the general purpose clock source on and
* off when in bypass.
*
* Passed
*
* struct SCCCntlMsgType {
* byte msgNum; /* SCC_Cntl msg = $06 */
* byte Driver; /* Dvr A = $00 Dvr B = $01 */
* byte GPI; /* GPI = 0 (Off) GPI = 1 (On) */
* }
*
* Returns
*
* struct SCCCntlErrType{
* byte errNum; /* NoErr = $00
* Error = -1
* */
* }
*
* Stack Info
* -----------------
* | Msg # * 32 |
* -----------------
* SP ->
*
* Register Y - contains message number starting at 1
*
*^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
SCC_Control Proc
Import Kern_Task : Code
Plx ; Restore X - msg number * 32
Phy
Lda ByPass_Flag ; This command only works in bypass.
Beq ERR
Stz RxMsgPage,x ; Assume no error.
Lda RxMsgPage+1,x ; Get the channel byte (DvrA or DvrB)
Cpa #DvrA ; Is it for DvrA or DvrB
Bne @Chck_B
Lda RxMsgPage+2,x ; Get the GPI
Bne @GPIA_On ; <> 0 means turn GPIA on
Lda SCC_Cntl ; Get the current value of the register.
And #≈RTXCA_GPIA ; Make the clock source for RTXCA 3.686 MHZ
Sta SCC_Cntl ; Store the new value
Bra Complete
@GPIA_On Lda #RTXCA_GPIA ; Get the bit mask.
Tsb SCC_Cntl ; Make the clock source for RTXCA GPIA
Bra Complete
@Chck_B Cpa #DvrB ; Was it Driver B
Bne ERR ; It is an error if it isn't.
Lda RxMsgPage+2,x ; Get the GPI
Bne @GPIB_On ; <> 0 means turn GPIB on
Lda SCC_Cntl ; Get the current value of the register
And #≈RTXCB_GPIA ; Make the clock source for RTXCB 3.686 MHZ
Sta SCC_Cntl ; Store the new value.
Bra Complete
@GPIB_On Lda #RTXCB_GPIA ; Get the bit mask.
Tsb SCC_Cntl ; Make the clock source for RTXB GPIB
Bra Complete
ERR Lda #Error ; We made a boo boo
Sta RxMsgPage,x ; Return the code
Complete Ply
Lda #MsgCmplt ; Tell host we've completed the message
Sta RxMsgState,y ; Store it in the message state variable
Lda #Int0 ; Load A with host interrupt bit
Tsb Int_Host
Jmp Kern_Task ; Return to wait for next event
endproc
*^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
*
* Kernel Subroutines called by indirect jump through table
* in the Zero Page
*
*^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
*^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
*
* Remv_RxMsgSgn - Install receive message signaller
*
* Register X - message number * 2 (msg numbers start at 1)
*
*^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
Remv_RxMsgSgn Proc
Import RxMsgSignal : Data
Export NullRxMsgSgn
Bcs Inst_RxMsgSgn
Ldy #>NullRxMsgSgn
Lda #<NullRxMsgSgn
*^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
*
* Inst_RxMsgSgn - Install receive message signaller
*
* Register X - message number * 2 (msg numbers start at 1)
* Register Y - High byte of message signaller address
* Register A - Low byte of message signaller address
*
*^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
Inst_RxMsgSgn Php ; Save the status byte
Sei
Sta RxMsgSignal-2,x ; Store the low byte of the msg handler
Inx
Tya
Sta RxMsgSignal-2,x ; Store the high byte of the msg handler
Plp ; Restore the status byte
Rts ; Return to caller
NullRxMsgSgn Rts
EndProc
*^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
*
* Remv_TxCmplSgn - Removel transmit completion signaller
*
* Register X - message number * 2 (msg numbers start at one)
*
*^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
Remv_TxCmplSgn Proc
Import TxMsgSignal : Data
Export NullTxCmplSgn
Bcs Inst_TxCmplSgn
Ldy #>NullTxCmplSgn
Lda #<NullTxCmplSgn
*^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
*
* Inst_TxCmplSgn - Install transmit completion signaller
*
* Register X - message number * 2 (msg numbers start at one)
* Register Y - High byte of completion handler
* Register A - Low byte of completion handler
*
*^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
Inst_TxCmplSgn Php
Sei
Sta TxMsgSignal-2,x ; Store the low byte of the msg handler
Tya
Sta TxMsgSignal-1,x ; Store the high byte of the msg handler
Plp
Rts ; Return to caller
NullTxCmplSgn Rts
EndProc
*^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
*
* Inst_Task - Install task. Always installs task after Kernel.
*
* Register X - TaskID of task to install
* Register Y - High byte of task address
* Register A - Low byte of task address
*
* Carry Clear - Branch to Kill Task
*
*^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
Inst_Task Proc
Import tPrev, \
tNext, \
tSp, \
tEvent, \
tWait : Data
Bcc Kill_Task
Php
Sei
Cpx #DvrA_ID
Beq Do_DvrA
Sta DvrB_Sp-1 ; Push the task address on the stack
Sty DvrB_Sp
Lda #<(DvrB_Sp-2) ; Init the stack pointer
Bra SkipA
Do_DvrA Sta DvrA_Sp-1 ; Push the task address on the stack
Sty DvrA_Sp
Lda #<(DvrA_Sp-2) ; Init the stack pointer
SkipA Sta tSp,x
Ldy #Kern_ID ; Insert the Task after the Kernel task
Lda tNext,y ; Get the Kernel's tNext link.
Sta tNext,x ; Make the new Task link to what the kernel
; was linked to.
Tay ; Make y-reg point to what the tNext of the Kernel
Txa ; Make a-reg the value of the one we are inserting
Sta tPrev,y ; Update the previous pointer of the task we are inserting
; in front of.
Ldy #Kern_ID
Sta tNext,y ; Make the Kernel TCB point to the new TCB
Tya ; Make a-reg point to Kernel
Sta tPrev,x ; Make tPrev of the task to be inserted
; point to the Kernel.
Lda #$80
Sta tEvent,x ; Set the Always Event
Sta tWait,x ; Wait for the Always event
Plp
Rts
*^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
*
* Kill_Task - Kill task.
*
* Register X - TaskID of the task to be removed. (ChanA_ID ChanB_ID only !)
*
*^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
Kill_Task
Php
Sei
Lda tPrev,x ; Get tPrev of task to be removed.
Tay ; y-reg points to task before the task to be removed.
Lda tNext,x ; Get tNext from task to be removed
Tax ; Make x-reg point to next task.
Sta tNext,y ; Make tNext of previous task point the task
; after the task to be removed.
Tya ; Make a-reg point to prev task
Sta tPrev,x ; Make tPrev of next task point to the tNext
; of the task that is removed.
Plp
Rts
EndProc
*^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
*
* Remv_ISR - remove an Interrupt service routine
*
* Register X - interrupt type
*
*^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
Remv_ISR Proc
Export Inst_ISR
Import UnKnown_Int : Code
Import ISR_Table :Data
Bcs Inst_ISR ; Is this a Remove or Install ISR call??
Ldy #>UnKnown_Int ; For Remove we fill in values for the
Lda #<Unknown_Int ; Unknown interrupt handler.
*^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
*
* Inst_ISR - make an entry into the interrupt table.
*
* Register X - interrupt type
* Register Y - High byte of interrupt address
* Register A - Low byte of interrupt address
*
*^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
Inst_ISR Php
Sei
Sta ISR_table,x ; Store the low byte of the address
Tya
Sta ISR_table+1,x ; Store the high byte of the address
Plp
Rts
endproc
*^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
*
* Remove_ISR - remove an Interrupt service routine
*
* Carry -> Set - install SCC ISR routine
* Clear - remove SCC ISR routine
*
* Register X - interrupt type
*
*^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
Remv_SCC_ISR Proc
Import UnKnown_SCCInt : Code
Import SCC_table : Data
Bcs Inst_SCC_ISR
Ldy #>UnKnown_Int
Lda #<Unknown_Int
*^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
*
* Inst_SCC_ISR - make an entry into the SCC interrupt table.
*
* Register X - interrupt type
* Register Y - High byte of interrupt address
* Register A - Low byte of interrupt address
*
*^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
Inst_SCC_ISR Php
Sei
Sta SCC_table,x ; Store the low byte of the address
Tya
Sta SCC_table+1,x ; Store the high byte of the address
Plp
Rts
endproc
*^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
*
* Reset Channel - reset channel A or B of the SCC
*
* Carry -> Set - reset A
* Clear - reset B
*
* A Register is corrupted
*
*^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
Reset_Chan Proc
Bcc ChanB ; Is this a ChanA or ChanB reset
Php ; Do ChanA reset
Sei
Lda #Wr_Reg9
Sta SCC_ACntl
Lda #ChanA_Reset|MIE|No_Vec
Sta SCC_ACntl
Plp
Rts
ChanB Php ; Do ChanB Reset
Sei
Lda #Wr_Reg9
Sta SCC_ACntl
Lda #ChanB_Reset|MIE|No_Vec
Sta SCC_ACntl
Plp
Rts
endproc
*^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
*
* Reg_Ver - register version info.
*
* Register A - Driver ID
* Register Y - High byte of info address
* Register X - Low byte of info address
*
*^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
Reg_Ver Proc
Phx
Asl A
Tax
Pla
Sta Ver_Ptr+1, x ; Store the Low byte of the address
Sty Ver_Ptr, x ; Store the High byte of the address
Rts
endproc
*^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
*
* Inst_TmTask - install a timer task.
*
* Carry -> Set - Branch to cancel timer task
* Clear - execute install timer task
*
* Register A - Low byte of parameter address
* Register X - High byte of the parameter address
*
*^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
Inst_TmTask Proc
Export Get_TMPB, \
Init_Timer, \
Timer_ISR
Php
Sei
Bcs Can_TmTask ; Cancel timer task if carry is set
Sta AddressLo ; Store the parameter address
Stx AddressHi
Ldy #$00
Lda (AddressLo),y
Tax
Iny
Lda (AddressLo),y ; Get the low byte of the completion routine
Sta TMPBpcL,x
Iny
Lda (AddressLo),y ; Get the high byte of the completion routine
Sta TMPBpcH,x
Iny
Lda (AddressLo),y ; Get the low byte of the time value
Sta TMPBTimeL,x
Iny
Lda (AddressLo),y ; Get the high byte of the time value
Sta TMPBTimeH,x
Txa
Tay
Jsr StartTimer
Plp
Rts
*^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
*
* Routine: Can_TmTask
* Inputs: Y - TMPB index
* Outputs: none
* Destroys: A, X, Y, n, v, z, c
* Size: 100 bytes
* Cycles: 15 - if it is already completed
* 50 - if it is the only running timer
* 98 + StopTimer + StartTimer - if head, with successors
* 65..94+ - if not head
* Stack Usage: 2 bytes
* Calls: Stop, Start
* Called by:
*
* Function: Cancels the timer in the indicated TMPB, and removes it
* from the timer queue.
*
* NOTE: This routine must be called with interrupts DISABLED
*
*^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
Can_TmTask
Lda TMPBcmplt,y ; Exit if the task has completed
Beq @Exit
Cpy tmReqQhead ; See if it is running
Bne @SrchQueue ; If not head of queue
Lda TMPBnext,y ; Check for successor
Bpl @HasSucc ; If not the only entry
Sta tmReqQhead ; Set head to nil
Lda #$00
Sta TMPBpcH,y ; Indicate that the routine is complete
Lda #Timer_Msk ; Disable timer interrupts
Trb Int_Mask ; Update the interrupt mask
Plp
Rts ; All done
@HasSucc Ldx tmReqQhead ; Get queue head
Jsr Stop ; Stop the head timer
Ldy tmReqQhead ; Get index of entry to dequeue
Lda #$00
Sta TMPBpcH,y ; Indicate that the routine is complete
Ldx TMPBnext,y ; Get index of successor
Stx tmReqQhead ; Successor is new head
Jsr @AdjTime ; Adjust the delay time
Jsr Start ; Start new head timer
Plp
Rts
@SrchQueue Lda tmReqQhead ; Index tmReqQhead
Sty tmIndexTemp
@loop Tax ; Load index register
Bmi @exit ; Exit if end of list (nil)
Lda TMPBnext,x ; Get index to next TMPB
Cpa tmIndexTemp ; Check for a match
Bne @loop ; Loop if not a match
Lda TMPBnext,y ; Prepare to un-link entry
Sta TMPBnext,x ; Finish unlinking it
Bmi @exit ; If entry has no successor
Tax
@AdjTime Clc ; Clear carry for addition
lda TMPBtimeL,x ; TMPBtime,x := TMPBtime,x + TMPBtime,y
Adc TMPBtimeL,y
Sta TMPBtimeL,x
Lda TMPBtimeH,x
Adc TMPBtimeH,y
Sta TMPBtimeH,x
@exit Plp
Rts ; All done
*^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
*
* Routine: StartTimer
* Inputs: Y - TMPB index
* Outputs: none
* Destroys: A, X, Y, n, v, z, c
* Size: 114 bytes
* Cycles: 39 + Start - if timer queue was empty
* 142 + Stop + StartTimer +..., otherwise
* Stack Usage: 2 bytes
* Calls: Stop, Start
* Called by:
*
* Function: Starts running the timer in the TMPB.
* The timeH and timeL fields of the TMPB must be filled in prior
* to this call.
*
* NOTE: This routine must be called with interrupts DISABLED
*
*^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
StartTimer
Lda #$ff
Sta TMPBcmplt,y ; Completion state is active
Ldx tmReqQhead ; Get index of head of list
Bpl @QNotEmpty ; If queue already has entries
Sty tmReqQhead ; New entry is queue head
Lda #nil ; Mark this entry as end of list
Sta TMPBnext,y ; Indicate no successor
Lda #Timer_Msk ; Enable timer interrupts
Tsb Int_Mask ; Update the interrupt mask
Tya ; Get TMPB index
Tax ; Setup TMPB index for StartTimer
Bra Start ; Start the timer and return
@QNotEmpty Jsr Stop ; Stop the currently running timer
Ldx tmReqQhead ; Index tmReqQhead
@loop Stx tmIndexTemp ; Remember index of previous TMPB
Lda TMPBnext,x ; Get index to next TMPB
Tax ; Load index register
Bmi @exit ; Exit if end of list (nil)
Sec ; Set carry for subtract
Lda TMPBtimeL,y ; TMPBtime,y := TMPBtime,y - TMPBtime,x
Sbc TMPBtimeL,x
Sta TMPBtimeL,y
Lda TMPBtimeH,y
Sbc TMPBtimeH,x
Sta TMPBtimeH,y
Bpl @loop ; Loop until TMPBtime,y is < 0
Clc ; Clear carry for addition
Lda TMPBtimeL,y ; TMPBtime,y := TMPBtime,y + TMPBtime,x
Adc TMPBtimeL,x
Sta TMPBtimeL,y
Lda TMPBtimeH,y
Adc TMPBtimeH,x
Sta TMPBtimeH,y
Sec ; Set carry for subtract
Lda TMPBtimeL,x ; TMPBtime,x := TMPBtime,x - TMPBtime,y
Sbc TMPBtimeL,y
Sta TMPBtimeL,x
Lda TMPBtimeH,x
Sbc TMPBtimeH,y
Sta TMPBtimeH,x
@exit Txa ; Prepare to store x
Sta TMPBnext,y ; Add rest of list after new entry
Ldx tmIndexTemp ; Get index of entry before new one
Tya ; Prepare to store y
Sta TMPBnext,x ; Add new entry after beginning of list
Ldx tmReqQhead ; Get index of head of list
*
* Falls into Start, which follows below
* bra Start ; Start the timer for the list head
*^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
*
* Routine: Start
* Inputs: X - tmReqQhead TMPB index
* Outputs: none
* Destroys: A, n, v, z, c
* Size: 75 bytes
* Cycles: 26 - when timer in range $8000..$FFFF
* 33 - when timer in range $0000..$007F
* 40 - when timer in range $0080..$00FF
* 43/49 - when timer in range $0100..$7FFF
* Stack Usage: 2 bytes
* Calls: none
* Called by: StartTmr, Timer_Int, CancelTmr
*
* Function: Loads the hardware timer with the amount of time remaining
* for the timer at the head of the timer queue, or $0080 if
* the amount is less than 1, or $7F80 if the value is greater
* than $007F. Adjusts the value in the TMPB to reflect the
* value loaded into the hardware time. The timer is then
* started and will interrupt when it reaches zero.
*
* NOTE: This routine must be called with interrupts DISABLED
*
*^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
Start
Lda TMPBtimeH,x ; Get high bits
Bne @OORangeH ; If way too big
Lda TMPBtimeL,x ; Get low bits
Bmi @OORangeL ; Not in range $0000..$007F
Stz TMPBtimeL,x ; Clear low bits
Sta TmCnt_Hi ; Start the counter
Lda #$FF ; Set latch to $FF to re-load timer
Sta TmLatch_Hi ; with $FF when timer runs out
Rts
@OORangeH Bmi @OORangeNeg ; If negative
Lda #$7F ; Load timer with $7F80
Sta TmCnt_Hi ; Start the counter
Lda #$FF ; Set latch to $FF to re-load timer
Sta TmLatch_Hi ; with $FF when timer runs out
Sec ; Set carry for subtract
Lda TMPBtimeL,x ; Get low bits
Sbc #$7F ; TMPBtime,x := TMPBtime,x - $007F
Sta TMPBtimeL,x
Bcs @exit ; If no borrow
Dec TMPBtimeH,x ; Adjust for borrow
@exit Rts
@OORangeNeg Stz TmCnt_Hi ; Use $0080 if negative
Lda #$FF ; Set latch to $FF to re-load timer
Sta TmLatch_Hi ; with $FF when timer runs out
Rts
@OORangeL Sec ; Set carry for subtract
Sbc #$7F ; TMPBtime,x := TMPBtime,x - $007F
Sta TMPBtimeL,x
Lda #$7F ; Load timer with $7F80
Sta TmCnt_Hi ; Start the counter
Lda #$FF ; Set latch to $FF to re-load timer
Sta TmLatch_Hi ; with $FF when timer runs out
Rts
*^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
*
* Routine: Stop
* Inputs: X - tmReqQhead TMPB index
* Outputs: n - indicates sign of TMPBtimer,x
* Destroys: A, v, z, c
* Size: 41 bytes
* Cycles: 38..40 + 9 if close to rollover
* Stack Usage: 2 bytes
* Calls: none
* Called by: StartTimer, Timer_Int, CancelTmr
*
* Function: Reads the hardware timer, and updates the head of the
* timer queue to reflect the actual amount of time remaining.
* It also returns an indication of the sign of the timer
* remaining for the queue head.
*
* NOTE: This routine must be called with interrupts DISABLED
*
*^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
Stop
Lda TmCnt_Lo ; Read low byte of counter
Cpa #$10 ; See if close to rollover
Blt Stop ; Wait if close to rollover
Lda TmCnt_Hi ; Read high byte of counter
Clc ; Clear carry for addition
Bpl @ZeroExt ; If high byte was positive
Adc TMPBtimeL,x ; Add to timer remaining for the
Sta TMPBtimeL,x ; Timer at head of the timer list
Bcs @TestSign ; If no borrow from high byte
Dec TMPBtimeH,x ; Adjust high byte
@TestSign Lda TMPBtimeH,x
Rts ; All done
@ZeroExt Adc TMPBtimeL,x ; Add to timer remaining for the
Sta TMPBtimeL,x ; Timer at head of the timer list
Bcc @TestSign ; If no carry into high byte
Inc TMPBtimeH,x ; Adjust high byte
Rts ; All done
*^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
*
* Routine: Timer_ISR
* Inputs: none
* Outputs: none
* Destroys: A, X, Y, n, v, z, c
* Size: 60 bytes
* Cycles: 15 + Stop + Start, if timer not fully expired
* 60 + Stop, if expired, no more queued,
* no completion handler
* 84 + Stop, if expired, no more queued,
* has completion handler
* 62 + Stop + Start, if expired, and more queued
* no completion handler
* 86 + Stop + Start, if expired, and more queued
* has completion handler
* Stack Usage: 2 bytes
* Calls: Stop, Start, TMPB completion handler
* Called by: Interrupt
*
* Function: Handles timer interrupts, determines if the timer at the
* head of the timer queue has fully expired, and calls the
* completion handler for that timer if one exists. Start
* any remaining timers on the timer queue.
*
* NOTE: This routine must be called with interrupts DISABLED
*
*^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
Timer_ISR
Ldx tmReqQhead ; Get index of head of list
Bmi @unknownint ; If timer queue is empty
Jsr Stop ; Stop timer and update queue head
Bpl Start ; If not expired, restart timer and exit
Phx ; Save pointer to dequeued entry
Stz TMPBcmplt,x ; Zero completion routine indicating done.
Lda TMPBnext,x ; Get next queue entry
Sta tmReqQhead ; Dequeue head
Bmi @DisTimer ; If no successor disable timer
Tax ; Get pointer to new queue head
Jsr Start ; Start next timer
Bra @RunCmplt ; Go run the completion routine
@DisTimer Lda #Timer_Msk ; Disable timer interrupts
Trb Int_Mask ; Update the interrupt mask
@RunCmplt Plx ; Restore pointer to dequeued entry
Lda TMPBpcL,x
Sta AddressLo
Lda TMPBpcH,x
Sta AddressHi
Jmp (AddressLo) ; Jump to the completion routine. The
; return address is on the stack
@unknownint Brk ; TMR interrupt with empty Q
*^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
*
* Routine: Get_TMPB
* Inputs: none
* Outputs: Y - TMPB index
* n - 1 if no free TMPBs available
* Destroys: A, Y, n, z
* Size: 22 bytes
* Cycles: 34 if BCPB was available
* 13 if BCPB was not available
* Stack Usage: 2 bytes
* Calls: none
* Called by:
*
* Function: Returns the index of a free TiMer Parameter Block
* (TMPB), and removes it from the list of free TMPBs.
* A flag is returned to indicate if a free TMPB existed.
*
* NOTE: This routine must be called with interrupts DISABLED.
*
*^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
Get_TMPB
Php
Sei
Bcs Free_TMPB
Ldy availhead ; Get the available list head
Bmi @exit ; If list empty
Lda TMPBnext,y ; Get successor
Sta availhead ; Update list head
@exit Plp
Rts ; All done
*^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
*
* Routine: Free_TMPB
* Inputs: Y - TMPB index
* Outputs: none
* Destroys: A, n, z, c
* Size: 19 bytes
* Cycles: 27
* Stack Usage: 2 bytes
* Calls: none
* Called by:
*
* Function: Adds the TMPB that was passed in, to the list of available
* TMPBs. If the TMPB is currently active, the system crashes
*
* NOTE: This routine must be called with interrupts DISABLED
*
*^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
Free_TMPB
Lda availhead ; Get the available list head
Sta TMPBnext,y ; Link it to end of new entry
Sty availhead ; New entry is new list head
Lda TMPBstate,y ; Check the state
Plp
Rts ; All done
*^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
*
* Routine: Init_Timer
* Inputs: none
* Outputs: none
* Destroys: A, X, n, v, z, c
* Size: 40 bytes
* Cycles: 45 + 14 per TMPB
* Stack Usage: 2 bytes
* Calls: none
* Called by: Reset
*
* Function: Initializes Timer data structures.
*
* NOTE: This routine must be called with interrupts DISABLED.
*
*^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
Init_Timer
last Equ TMPBsize*(MaxTMPBs-1)
Lda #0 ; Index of first TMPB
Sta availhead ; All TMPBs are now available
Clc ; Clear carry for additions
@loop Tax ; Setup index register
Adc #TMPBsize ; Point to next TMPB
Sta TMPBnext,x ; Have previous point to next
Stz TMPBcmplt,x ; Zero the completion state
Cpa #last ; Check for last TMPB
Blt @loop ; Process next TMPB
Lda #nil ; Mark empty lists
Sta last+TMPBnext ; Mark end of free list
Sta tmReqQhead ; Request queue head is empty
Lda #Timer_Msk ; Disable timer interrupts
Trb Int_Mask ; Update the interrupt mask
Lda #One_Shot ; Prepare to force one shot mode
Trb TD_Cntl ; Reset the bit
Lda #$80 ; Low byte latch is a constant
Sta TmLatch_Lo ; Initialize the low timer latch
Rts
*
* TiMer Parameter Block (TMPB)
*
TMPBnext DS.B 1 ; Next TMPB on list
TMPBstate DS.B 1 ; Request state
TMPBtimeH DS.B 1 ; High byte of 2 byte timer
TMPBtimeL DS.B 1 ; Low byte of 2 byte timer
TMPBpcH DS.B 1 ; Completion routine PC high
TMPBpcL DS.B 1 ; Completion routine PC low
TMPBcmplt DS.B 1 ; Completion state (0 = complete 0<> means running)
DS.B TMPBsize*(MaxTMPBs-1) ; Allocate remaining TMPBs
availhead DS.B 1 ; Head of TMPB free list
tmReqQhead DS.B 1 ; Head of TMPB request queue
tmIndexTemp DS.B 1 ; Temporary storage for index
endproc
*^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
*
* Global Data Area for kernel
*
*^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
Global_Kernel Proc
Export ISR_table, \
ISR_Decode, \
MsgNumTimes2, \
MsgNumTimes32, \
Cmd_Table, \
Cmd_JmpTable, \
SCC_Table, \
TxMsgSignal, \
RxMsgSignal, \
tPrev, \
tNext, \
tSp, \
tEvent, \
tWait, \
tTNxt, \
tTEvent, \
tTISR, \
VerInfo
Import Remv_RxMsgSgn, \
Remv_TxCmplSgn, \
Remv_ISR, \
Remv_SCC_ISR, \
Inst_Task, \
Rel_Task, \
Ev_Wait, \
Ev_Signal, \
Ev_Reset, \
TEv_Reset, \
Get_TMPB, \
Inst_TmTask, \
Reg_Ver, \
NullRxMsgSgn, \
NullTxCmplSgn, \
UnKnown_Int, \
UnKnown_SCCInt, \
Dsptch_KRxMsg
*
* TCB - Task Control Block
*
* Each active task has a TCB entry in the TCB linked list.
* The List starts out with only one active task which is the kernel task.
* The Kernel is always active.
*
tPrev DC.B Kern_ID ; Previous Task
tNext DC.B Kern_ID ; Next task ID (initially 0 for Kernel Task only)
tSp DC.B $FF ; Stack Pointer for this task
tEvent DC.B $80 ; Event flags (bit 7 event always active)
tWait DC.B $00 ; Event Mask (Wait for RxMsg1 event always)
TCB_Size Equ *-tPrev
DC.B $00 ; tPrev ChanA Task
DC.B $00 ; tNext ChanA Task
DC.B $a9 ; tSp ChanA Task
DC.B $80 ; tEvent ChanA Task (bit 7 event always active)
DC.B $00 ; tWait ChanA Task
DC.B $00 ; tPrev ChanB Task
DC.B $00 ; tNext ChanB Task
DC.B $54 ; tSp ChanB Task
DC.B $80 ; tEvent ChanB Task (bit 7 event always active)
DC.B $00 ; tWait ChanB Task
*
* 6502 and SCC interrupt service routine vector tables
*
ISR_table DC.W Unknown_Int ; 0 priority
DC.W UnKnown_Int ; DMA1
DC.W Unknown_Int ; DMA2
DC.W UnKnown_Int ; SCC
DC.W UnKnown_Int ; Timer
DC.W UnKnown_Int ; Host
ISR_Decode DC.B 0 ; %00000000
DC.B 0
DC.B DMA1 ; %00000010
DC.B 0
DC.B DMA2 ; %00000100
DC.B 0
DC.B DMA2 ; %00000110
DC.B 0
DC.B SCC ; %00001000
DC.B 0
DC.B SCC ; %00001010
DC.B 0
DC.B SCC ; %00001100
DC.B 0
DC.B SCC ; %00001110
DC.B 0
DC.B HOST ; %00010000
DC.B 0
DC.B DMA1 ; %00010010
DC.B 0
DC.B DMA2 ; %00010100
DC.B 0
DC.B DMA2 ; %00010110
DC.B 0
DC.B SCC ; %00011000
DC.B 0
DC.B SCC ; %00011010
DC.B 0
DC.B SCC ; %00011100
DC.B 0
DC.B SCC ; %00011110
DC.B 0
DC.B TIMER ; %00100000
DC.B 0
DC.B DMA1 ; %00100010
DC.B 0
DC.B DMA2 ; %00100100
DC.B 0
DC.B DMA2 ; %00100110
DC.B 0
DC.B SCC ; %00101000
DC.B 0
DC.B SCC ; %00101010
DC.B 0
DC.B SCC ; %00101100
DC.B 0
DC.B SCC ; %00101110
DC.B 0
DC.B TIMER ; %00110000
DC.B 0
DC.B DMA1 ; %00110010
DC.B 0
DC.B DMA2 ; %00110100
DC.B 0
DC.B DMA2 ; %00110110
DC.B 0
DC.B SCC ; %00111000
DC.B 0
DC.B SCC ; %00111010
DC.B 0
DC.B SCC ; %00111100
DC.B 0
DC.B SCC ; %00111110
SCC_table DC.W UnKnown_SCCInt
DC.W UnKnown_SCCInt
DC.W UnKnown_SCCInt
DC.W UnKnown_SCCInt
DC.W UnKnown_SCCInt
DC.W UnKnown_SCCInt
DC.W UnKnown_SCCInt
DC.W UnKnown_SCCInt
*
* Transmit message Request Completion signal routines
*
TxMsgSignal DC.W NullTxCmplSgn
DC.W NullTxCmplSgn
DC.W NullTxCmplSgn
DC.W NullTxCmplSgn
DC.W NullTxCmplSgn
DC.W NullTxCmplSgn
DC.W NullTxCmplSgn
*
* Receive new message signal routines
*
RxMsgSignal DC.W NullRxMsgSgn
DC.W NullRxMsgSgn
DC.W NullRxMsgSgn
DC.W NullRxMsgSgn
DC.W NullRxMsgSgn
DC.W NullRxMsgSgn
DC.W NullRxMsgSgn
*
* Kernel Command Table - this contains the addresses of the kernel commands
* which will later be tranfered to the zero page,
* Up to twenty commands are supported. They must be
* in order of their command numbers.
*
Cmd_Table DC.W Remv_RxMsgSgn
DC.W Remv_TxCmplSgn
DC.W Remv_ISR
DC.W Remv_SCC_ISR
DC.W Inst_Task
DC.W Rel_Task
DC.W Ev_Wait
DC.W Ev_Signal
DC.W Ev_Reset
DC.W Reset_Chan
DC.W Get_TMPB
DC.W Inst_TmTask
DC.W Reg_Ver
DS.W 7
Cmd_JmpTable Jmp (Krn_CmdBase+(RemvRxMsg*2))
Jmp (Krn_CmdBase+(RemvTxCmpl*2))
Jmp (Krn_CmdBase+(RemvISR*2))
Jmp (Krn_CmdBase+(RemvSCCISR*2))
Jmp (Krn_CmdBase+(InstTask*2))
Jmp (Krn_CmdBase+(RelTask*2))
Jmp (Krn_CmdBase+(WaitEvent*2))
Jmp (Krn_CmdBase+(SignalTask*2))
Jmp (Krn_CmdBase+(ResetEvent*2))
Jmp (Krn_CmdBase+(ResetChan*2))
Jmp (Krn_CmdBase+(GetTMPB*2))
Jmp (Krn_CmdBase+(InstTmTask*2))
Jmp (Krn_CmdBase+(RegVer*2))
MsgNumTimes2 DC.B 0,2,4,6,8,10,12,14
MsgNumTimes32 DC.B 0,32,64,96,128,160,192,224
*
* Version Information
*
String Pascal
VerInfo DC.B $02
DC.B 'Enhanced Communications Controller'
DC.B 'Version 1.0A0 © Apple Computer Inc. 1988'
DCB.W 512, $00FF ; Needed for AURORA ROM resource padding
endproc
End