izapple2/cardInOut.go
2021-01-24 23:25:52 +01:00

173 lines
3.4 KiB
Go

package izapple2
import (
"bufio"
"fmt"
"os"
)
/*
In out card experiment to interface with the emulator host.
See:
"Apple II Monitors peeled."
http://mysite.du.edu/~etuttle/math/acia.htm
PR#n stores Cn00 in CSWL and CSWH
IN#n stores Cn00 in KSWL and KSWH
*/
// CardInOut is an experimental card to bridge with the host console
type CardInOut struct {
cardBase
reader *bufio.Reader
}
// NewCardInOut creates CardInOut
func NewCardInOut() *CardInOut {
var c CardInOut
c.name = "Card to test I/O"
return &c
}
func (c *CardInOut) assign(a *Apple2, slot int) {
c.addCardSoftSwitchR(0, func(*ioC0Page) uint8 {
if c.reader == nil {
c.reader = bufio.NewReader(os.Stdin)
}
value, err := c.reader.ReadByte()
if err != nil {
panic(err)
}
value += 0x80
if value&0x7f == 10 {
value = 13 + 0x80
}
//fmt.Printf("[cardInOut] Read access to softswith 0x%x for slot %v, value %x.\n", 0, slot, value)
return value
}, "INOUTR")
c.addCardSoftSwitchW(1, func(_ *ioC0Page, value uint8) {
//fmt.Printf("[cardInOut] Write access to softswith 0x%x for slot %v, value 0x%x: %v, %v.\n", 1, slot, value, value&0x7f, string(value&0x7f))
if value&0x7f == 13 {
fmt.Printf("\n")
} else {
fmt.Printf("%v", string(value&0x7f))
}
}, "INOUTW")
data := buildBaseInOutRom(slot)
c.romCsxx = newMemoryRangeROM(0xC200, data[:], "InOUt card")
c.cardBase.assign(a, slot)
}
func buildBaseInOutRom(slot int) []uint8 {
data := [256]uint8{
// Register
0x4c, 0x40, 0xc2, 0, 0, 0, 0, 0,
0, 0, 0, 0, 0, 0, 0, 0,
0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
0x48, 0xA5, 0x38, 0xD0, 0x11, 0xA9, 0xC2, 0xC5,
0x39, 0xD0, 0x0B, 0xAD, 0x4F, 0x85, 0x38, 0x68,
0x91, 0x28, 0xAD, 0xA0, 0xC0, 0x60, 0x68, 0x8D,
0xA1, 0xC0, 0x60,
}
// Fix slot dependant addresses
data[0x02] = uint8(0xc0 + slot)
data[0x46] = uint8(0xc0 + slot)
data[0x53] = uint8(0x80 + slot<<4)
data[0x58] = uint8(0x81 + slot<<4)
return data[:]
}
/*
The ROM code was assembled using https://www.masswerk.at/6502/assembler.html
We will have $Cn00 as the entry point for CSWL/H. But before doing
anything we have to check that we are not in $Cn00 because of an IN#.
To da that we check id KSWL/H is $Cn00, it is it we wif it to INEntry.
src:
BASL = $28
KSWL = $38
KSWH = $39
* = $C200
Entry:
JMP SkipHeader
* = $C240
SkipHeader:
PHA
LDA *KSWL
BNE PREntry
LDA #$C2
CMP *KSWH
BNE PREntry
FixKSWL:
LDA #<INEntry
STA *KSWL
INEntry:
PLA
STA (BASL),Y
LDA $C0A0
RTS
PREntry:
PLA
STA $C0A1
RTS
Listing:
pass 2
0000 BASL = 0028
0000 KSWL = 0038
0000 KSWH = 0039
* = $C200
C200 ENTRY:
C200 JMP SKIPHE 4C 40 C2
* = $C240
C240 SKIPHE
C240 PHA 48
C241 LDA *KSWL A5 38
C243 BNE PRENTR D0 11
C245 LDA #$C2 A9 C2
C247 CMP *KSWH C5 39
C249 BNE PRENTR D0 0B
C24B LDA #<INENTR A9 4F
C24D STA *KSWL 85 38
C24F INENTR
C24F PLA 68
C250 STA (BASL),Y 91 28
C252 LDA $C0A0 AD A0 C0
C255 RTS 60
C256 PRENTR
C256 PLA 68
C257 STA $C0A1 8D A1 C0
C25A RTS 60
done.
Object Code:
c200:
4C 40 C2
c240:
48 A5 38 D0 11
A9 C2 C5 39 D0 0B A9 4F
85 38 68 91 28 AD A0 C0
60 68 8D A1 C0 60
*/