1. Re: including ISR in euphoria program
to Robert Craig,
As I'm writing an include file to play wave file on sound blaster card
I'm stock with a bug regarding the interrupt service routine. it's
doesn't work.
I need to known if ISR are running in protected mode or real, or virtual
mode
Here is my ISR code.
**************** DSP_INT.E *********************************
-- DSP_INT.E is interrupt code
-- to include in playwave.e
constant END_OF_INT = #20 -- end of interrupt command for PIC
global constant PIC1_MASK_REG = #21 -- mask register I/O port for PIC 1
global constant PIC2_MASK_REG = #A1 -- mask register I/O port for PIC 2
global constant PIC1_MODE = #20 -- interrupt mode register I/O port for
PIC 1
global constant PIC2_MODE = #A0 -- interrupt mode register I/O port for
PIC 2
sequence ISRCode
-- 1) increment dMA_END flag to inform euphoria code that transfert is
complete
-- 2) reset DSP interrupt flag
-- 3) reset interrupt controller (master and slave PIC)
ISRCode = {
#50, -- PUSH AX
#52, -- PUSH DX
#FE,#06,#00,#26, -- INC [DoneFlag] ; transfert ended
#8B,#16,#00,#23, -- MOV DX, [BASE_IO]
#83,#C2,#0E, -- ADD DX, 0E ; DSP_READ_STATUS
#EC, -- IN AL, DX
#BA,#00,#20, -- MOV DX, PIC1_MODE ; master pic
address
#B0,#20, -- MOV AL, END_OF_INT
#EE, -- OUT DX, AL ;send EOI to
master PIC
#80,#3E,#00,#25,#07, -- CMP [IRQ_NB], 7
#76,#04, -- JBE @SORTIE
#BA,#00,#A0, -- MOV DX, PIC2_MODE ;slave pic address
#EE, -- OUT DX, AL ;send EOI to slave
PIC
-- @SORTIE:
#5A, -- POP DX
#58, -- POP AX
#FB, -- STI ;enable interrupt
#CF, -- IRET
#00,#00, -- BASE_IO DW 0
#00, -- IRQ_NB DB 0
#00 -- DoneFlag DB 0
} -- ISRCode
global atom pEND_FLAG, pIRQ_NB, pBASE_IO
pEND_FLAG = length(ISRCode) - 1 -- flag end of play modified by ISR
pIRQ_NB = length(ISRCode) - 2 -- store interrupt number
pBASE_IO = length(ISRCode) - 3 -- store DSP base I/O port
