Waz monitor in asm format

This commit is contained in:
Stefano Furiosi 2016-06-18 14:11:22 -07:00
parent c893083d62
commit f8e908eb6b
4 changed files with 263 additions and 2 deletions

3
.gitignore vendored
View File

@ -1,3 +1,6 @@
.pioenvs
.clang_complete
.gcc-flags.json
*.sym
*.o
*.lst

258
ASM/woz_monitor_masm.asm Normal file
View File

@ -0,0 +1,258 @@
; dasm woz_monitor_masm.asm -orom.o -lrom.lst -srom.sym
;-------------------------------------------------------------------------
;
; The WOZ Monitor for the Apple 1
; Written by Steve Wozniak 1976
;
;-------------------------------------------------------------------------
processor 6502
org $FF00
;-------------------------------------------------------------------------
; Memory declaration
;-------------------------------------------------------------------------
XAML equ $24 ;Last "opened" location Low
XAMH equ $25 ;Last "opened" location High
STL equ $26 ;Store address Low
STH equ $27 ;Store address High
L equ $28 ;Hex value parsing Low
H equ $29 ;Hex value parsing High
YSAV equ $2A ;Used to see if hex value is given
MODE equ $2B ;$00=XAM, $7F=STOR, $AE=BLOCK XAM
IN equ $0200,$027F ;Input buffer
KBD equ $D010 ;PIA.A keyboard input
KBDCR equ $D011 ;PIA.A keyboard control register
DSP equ $D012 ;PIA.B display output register
DSPCR equ $D013 ;PIA.B display control register
; KBD b7..b0 are inputs, b6..b0 is ASCII input, b7 is constant high
; Programmed to respond to low to high KBD strobe
; DSP b6..b0 are outputs, b7 is input
; CB2 goes low when data is written, returns high when CB1 goes high
; Interrupts are enabled, though not used. KBD can be jumpered to IRQ,
; whereas DSP can be jumpered to NMI.
;-------------------------------------------------------------------------
; Constants
;-------------------------------------------------------------------------
BS equ $DF ;Backspace key, arrow left key
CR equ $8D ;Carriage Return
ESC equ $9B ;ESC key
PROMPT equ "\" ;Prompt character
;-------------------------------------------------------------------------
; Let's get started
;
; Remark the RESET routine is only to be entered by asserting the RESET
; line of the system. This ensures that the data direction registers
; are selected.
;-------------------------------------------------------------------------
RESET CLD ;Clear decimal arithmetic mode
CLI
LDY #%01111111 ;Mask for DSP data direction reg
STY DSP ;(DDR mode is assumed after reset)
LDA #%10100111 ;KBD and DSP control register mask
STA KBDCR ;Enable interrupts, set CA1, CB1 for
STA DSPCR ;positive edge sense/output mode.
; Program falls through to the GETLINE routine to save some program bytes
; Please note that Y still holds $7F, which will cause an automatic Escape
;-------------------------------------------------------------------------
; The GETLINE process
;-------------------------------------------------------------------------
NOTCR CMP #BS ;Backspace key?
BEQ BACKSPACE ;Yes
CMP #ESC ;ESC?
BEQ ESCAPE ;Yes
INY ;Advance text index
BPL NEXTCHAR ;Auto ESC if line longer than 127
ESCAPE LDA #PROMPT ;Print prompt character
JSR ECHO ;Output it.
GETLINE LDA #CR ;Send CR
JSR ECHO
LDY #0+1 ;Start a new input line
BACKSPACE DEY ;Backup text index
BMI GETLINE ;Oops, line's empty, reinitialize
NEXTCHAR LDA KBDCR ;Wait for key press
BPL NEXTCHAR ;No key yet!
LDA KBD ;Load character. B7 should be '1'
STA IN,Y ;Add to text buffer
JSR ECHO ;Display character
CMP #CR
BNE NOTCR ;It's not CR!
; Line received, now let's parse it
LDY #-1 ;Reset text index
LDA #0 ;Default mode is XAM
TAX ;X=0
SETSTOR ASL ;Leaves $7B if setting STOR mode
SETMODE STA MODE ;Set mode flags
BLSKIP INY ;Advance text index
NEXTITEM LDA IN,Y ;Get character
CMP #CR
BEQ GETLINE ;We're done if it's CR!
CMP #"."
BCC BLSKIP ;Ignore everything below "."!
BEQ SETMODE ;Set BLOCK XAM mode ("." = $AE)
CMP #":"
BEQ SETSTOR ;Set STOR mode! $BA will become $7B
CMP #"R"
BEQ RUN ;Run the program! Forget the rest
STX L ;Clear input value (X=0)
STX H
STY YSAV ;Save Y for comparison
; Here we're trying to parse a new hex value
NEXTHEX LDA IN,Y ;Get character for hex test
EOR #$B0 ;Map digits to 0-9
CMP #9+1 ;Is it a decimal digit?
BCC DIG ;Yes!
ADC #$88 ;Map letter "A"-"F" to $FA-FF
CMP #$FA ;Hex letter?
BCC NOTHEX ;No! Character not hex
DIG ASL
ASL ;Hex digit to MSD of A
ASL
ASL
LDX #4 ;Shift count
HEXSHIFT ASL ;Hex digit left, MSB to carry
ROL L ;Rotate into LSD
ROL H ;Rotate into MSD's
DEX ;Done 4 shifts?
BNE HEXSHIFT ;No, loop
INY ;Advance text index
BNE NEXTHEX ;Always taken
NOTHEX CPY YSAV ;Was at least 1 hex digit given?
BEQ ESCAPE ;No! Ignore all, start from scratch
BIT MODE ;Test MODE byte
BVC NOTSTOR ;B6=0 is STOR, 1 is XAM or BLOCK XAM
; STOR mode, save LSD of new hex byte
LDA L ;LSD's of hex data
STA (STL,X) ;Store current 'store index'(X=0)
INC STL ;Increment store index.
BNE NEXTITEM ;No carry!
INC STH ;Add carry to 'store index' high
TONEXTITEM JMP NEXTITEM ;Get next command item.
;-------------------------------------------------------------------------
; RUN user's program from last opened location
;-------------------------------------------------------------------------
RUN JMP (XAML) ;Run user's program
;-------------------------------------------------------------------------
; We're not in Store mode
;-------------------------------------------------------------------------
NOTSTOR BMI XAMNEXT ;B7 = 0 for XAM, 1 for BLOCK XAM
; We're in XAM mode now
LDX #2 ;Copy 2 bytes
SETADR LDA L-1,X ;Copy hex data to
STA STL-1,X ; 'store index'
STA XAML-1,X ; and to 'XAM index'
DEX ;Next of 2 bytes
BNE SETADR ;Loop unless X = 0
; Print address and data from this address, fall through next BNE.
NXTPRNT BNE PRDATA ;NE means no address to print
LDA #CR ;Print CR first
JSR ECHO
LDA XAMH ;Output high-order byte of address
JSR PRBYTE
LDA XAML ;Output low-order byte of address
JSR PRBYTE
LDA #":" ;Print colon
JSR ECHO
PRDATA LDA #" " ;Print space
JSR ECHO
LDA (XAML,X) ;Get data from address (X=0)
JSR PRBYTE ;Output it in hex format
XAMNEXT STX MODE ;0 -> MODE (XAM mode).
LDA XAML ;See if there's more to print
CMP L
LDA XAMH
SBC H
BCS TONEXTITEM ;Not less! No more data to output
INC XAML ;Increment 'examine index'
BNE MOD8CHK ;No carry!
INC XAMH
MOD8CHK LDA XAML ;If address MOD 8 = 0 start new line
AND #%00000111
BPL NXTPRNT ;Always taken.
;-------------------------------------------------------------------------
; Subroutine to print a byte in A in hex form (destructive)
;-------------------------------------------------------------------------
PRBYTE PHA ;Save A for LSD
LSR
LSR
LSR ;MSD to LSD position
LSR
JSR PRHEX ;Output hex digit
PLA ;Restore A
; Fall through to print hex routine
;-------------------------------------------------------------------------
; Subroutine to print a hexadecimal digit
;-------------------------------------------------------------------------
PRHEX AND #%00001111 ;Mask LSD for hex print
ORA #"0" ;Add "0"
CMP #"9"+1 ;Is it a decimal digit?
BCC ECHO ;Yes! output it
ADC #6 ;Add offset for letter A-F
; Fall through to print routine
;-------------------------------------------------------------------------
; Subroutine to print a character to the terminal
;-------------------------------------------------------------------------
ECHO BIT DSP ;DA bit (B7) cleared yet?
BMI ECHO ;No! Wait for display ready
STA DSP ;Output character. Sets DA
RTS
;-------------------------------------------------------------------------
; Vector area
;-------------------------------------------------------------------------
dc.w $0000 ;Unused, what a pity
NMI_VEC dc.w $0F00 ;NMI vector
RESET_VEC dc.w RESET ;RESET vector
IRQ_VEC dc.w $0000 ;IRQ vector
;-------------------------------------------------------------------------

View File

@ -9,7 +9,7 @@
+--- 3k3 ----- 2| RDY PHI2O |39
| 3| PHI1O SOB |38
+--- 3k3 ----- 4| IRQ PHI2 |37 -------- 52
| 5| MLB BE |36
| 5| MLB BE |36---3k3----3.3v
+--- 3k3 ----- 6| /NMI NC |35
| 7| SYNC R/W |34 -------- 53
+------------- 8| VDD D0 |33 -------- 30

View File

@ -8,7 +8,7 @@ const int SERIAL_SPEED = 115200; // Arduino Serial Speed
const int CLOCK_PIN = 52; // TO 6502 CLOCK
const int RW_PIN = 53; // TO 6502 R/W
const int CLOCK_DELAY = 4; // HIGH / LOW CLOCK STATE DELAY
const int CLOCK_DELAY = 3; // HIGH / LOW CLOCK STATE DELAY
const char SERIAL_BS = 0x08;