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Disable IRQ if opening at 115200 bps

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This commit is contained in:
Colin Leroy-Mira 2024-02-19 18:27:34 +01:00 committed by Oliver Schmidt
parent 7a12399b39
commit 3fd78208ba
3 changed files with 18 additions and 2 deletions
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5
doc/apple2.sgml
View File

@ -452,10 +452,15 @@ The names in the parentheses denote the symbols to be used for static linking of
(RTS/CTS) and does interrupt driven receives. Speeds faster than 9600 baud
aren't reachable because the ROM and ProDOS IRQ handlers are too slow.
Software flow control (XON/XOFF) is not supported.
Note that because of the peculiarities of the 6551 chip transmits are not
interrupt driven, and the transceiver blocks if the receiver asserts
flow control because of a full buffer.
Note that using the driver at SER_BAUD_115200 will disable IRQs. It will be up
to the users to use the serial port, either by re-enabling IRQs themselves,
or by directly poll-reading the ACIA DATA register without the help of ser_get().
The driver defaults to slot 2. Call <tt/ser_apple2_slot()/ prior to
<tt/ser_open()/ in order to select a different slot. <tt/ser_apple2_slot()/
succeeds for all Apple&nbsp;II slots, but <tt/ser_open()/ fails with

5
doc/apple2enh.sgml
View File

@ -453,10 +453,15 @@ The names in the parentheses denote the symbols to be used for static linking of
(RTS/CTS) and does interrupt driven receives. Speeds faster than 9600 baud
aren't reachable because the ROM and ProDOS IRQ handlers are too slow.
Software flow control (XON/XOFF) is not supported.
Note that because of the peculiarities of the 6551 chip transmits are not
interrupt driven, and the transceiver blocks if the receiver asserts
flow control because of a full buffer.
Note that using the driver at SER_BAUD_115200 will disable IRQs. It will be up
to the users to use the serial port, either by re-enabling IRQs themselves,
or by directly poll-reading the ACIA DATA register without the help of ser_get().
The driver defaults to slot 2. Call <tt/ser_apple2_slot()/ prior to
<tt/ser_open()/ in order to select a different slot. <tt/ser_apple2_slot()/
succeeds for all Apple&nbsp;II slots, but <tt/ser_open()/ fails with

10
libsrc/apple2/ser/a2.ssc.s
View File

@ -302,6 +302,7 @@ HandshakeOK:
lda (ptr1),y ; Baudrate index
tay
lda BaudTable,y ; Get 6551 value
sta tmp2 ; Backup for IRQ setting
bpl BaudOK ; Check that baudrate is supported
lda #SER_ERR_BAUD_UNAVAIL
@ -332,8 +333,13 @@ BaudOK: sta tmp1
ora #%00000001 ; Set DTR active
sta RtsOff ; Store value to easily handle flow control later
ora #%00001000 ; Enable receive interrupts (RTS low)
sta ACIA_CMD,x
ora #%00001010 ; Disable interrupts and set RTS low
ldy tmp2 ; Don't enable IRQs if 115200bps
beq :+
and #%11111101 ; Enable receive IRQs
: sta ACIA_CMD,x
; Done
stx Index ; Mark port as open