Hi all,

How do i Acess a isa card from the sprinter ?

I wanted to control a ISA serial interface , on the PC is quite easy, but how do i do it on my beloved sprinter ?

thanks

Jorge

If you want to interaction with ISA devices, you have to make following
steps:
1) send 10h value to port 1FFDh(system port);
2) send control byte to port 0E2h(third memory window port);
control byte:
D7...should be 1
D6...should be 1
D5...should be 0
D4...should be 1
D3...should be 0
D2...specify number of ISA slot
D1...specify access mode (0 - ISA memory, 1 - ISA ports)
D0...should be 0

The read/write signals are forming from read/write signals memory range
0C000h-0FFFFh.
And the address lines A13...A0 has taken from processor data-BUS. The
other
ISA-signals such as RESET, AEN, A19...A14 can be set in port 9FBDh. And
default
value is 00h.
port 9FBDh:
D7...RESET
D6...AEN
D5...A19
D4...A18
D3...A17
D2...A16
D1...A15
D0...A14

ISA_DIR      EQU 9FBDh

SC_PORT      EQU 1FFDh

PAGE3        EQU 0E2h



SAVE_PAGE    DB 0           ;variable for previous status of third memory
port



RESET_ISA:                  ; reset ISA device

        LD C, ISA_DIR

        LD A,0C0h

        OUT (C),A

	CALL Pause_10ms

        LD A,0

        OUT (C),A

        RET



Pause_10ms:

        LD HL,10000

Loop:

        DEC HL

        LD A,H

        XOR L

        JR NZ,Loop

        RET



OPEN_ISA_PORTS:             ; open access to ISA

        LD BC,SC_PORT

        LD A,10h

        OUT (C),A

        IN A,(PAGE3)        ; read value from memory port

        LD (SAVE_PAGE),A    ; save previous status of memory port

        LD A,0D2h           ; control byte for (first (upper) ISA slot)

        OUT (PAGE3), A      ; opening ISA port address space

        LD C,ISA_DIR

        LD A,0              ; high ISA addresses RESET and AEN signals.

        OUT (C),A

        RET



CLOSE_ISA_PORTS:            ; close access to ISA

        LD A,(SAVE_PAGE)

        OUT (PAGE3),A       ; restore value of memory port

        LD BC,SC_PORT

        LD A,0

        OUT (C),A           ;

        RET



WRITE_ISA_PORT:

        LD HL,ADRESS_PORT+0C000h     ; ISA port address + 0C000h offset 3

memory page

        LD A,DATA_OUT                ; data for writing

        LD (HL),A                    ; write data to port which pointered
HL

        RET



READ_ISA_PORT:

        LD HL, ADRESS_PORT+0C000h    ; ISA port address + 0C000h offset 3

memory page

        LD A,(HL)                    ; read data from port which pointered
HL

        RET