package apple2 import ( "fmt" ) /* In out card experiment to interface with the emulator host. See: "Apple II Monitors peeled." http://mysite.du.edu/~etuttle/math/acia.htm */ type cardInOut struct { cardBase i int } func (c *cardInOut) assign(a *Apple2, slot int) { for i := uint8(0x0); i <= 0xf; i++ { iCopy := i c.addCardSoftSwitchR(i, func(*ioC0Page) uint8 { value := []uint8{0xc1, 0xc1, 0x93, 0x0}[c.i%4] c.i++ fmt.Printf("[cardInOut] Read access to softswith 0x%x for slot %v, value %x.\n", iCopy, slot, value) //return 0x41 + 0x80 return []uint8{0x41, 0x41, 0x13}[i%3] + 0x80 }, "INOUTR") c.addCardSoftSwitchW(i, func(_ *ioC0Page, value uint8) { fmt.Printf("[cardInOut] Write access to softswith 0x%x for slot %v, value 0x%x.\n", iCopy, slot, value) }, "INOUTW") } in := true out := false data := [256]uint8{ // Register 0xA9, 0xC2, 0x85, 0x37, 0x85, 0x39, 0xA9, 0x10, 0x85, 0x36, 0xA9, 0x15, 0x85, 0x38, 0x60, 0xEA, // Out char 0x8D, 0xA1, 0xC0, 0x60, 0xEA, // Get char 0x91, 0x28, 0xAD, 0xA0, 0xC0, 0x60, } if !out { // NOP the CSWL,H change for _, v := range []uint8{2, 3, 8, 9} { data[v] = 0xEA } } if !in { // NOP the KSWL,H change for _, v := range []uint8{4, 5, 12, 13} { data[v] = 0xEA } } c.rom = newMemoryRange(0xC200, data[0:255]) if slot != 2 { // To make ifwork on other slots, patch C2, A0 and A1 panic("Assert failed. Only slot 2 supported for the InOut card") } c.cardBase.assign(a, slot) } /* The ROM code was assembled using https://www.masswerk.at/6502/assembler.html src: BASL = $28 CSWL = $36 CSWH = $37 KSWL = $38 KSWH = $39 * = $C200 Register: LDA #$C2 STA *CSWH STA *KSWH LDA #$10 STA *CSWL LDA #$15 STA *KSWL RTS NOP OutChar: STA $C0A1 RTS NOP GetChar: STA (BASL),Y LDA $C0A0 RTS assembled as: 0000 BASL = 0028 0000 CSWL = 0036 0000 CSWH = 0037 0000 KSWL = 0038 0000 KSWH = 0039 * = $C200 C200 REGIST C200 LDA #$C2 A9 C2 C202 STA *CSWH 85 37 C204 STA *KSWH 85 39 C206 LDA #$10 A9 10 C208 STA *CSWL 85 36 C20A LDA #$15 A9 15 C20C STA *KSWL 85 38 C20E RTS 60 C20F NOP EA C210 OUTCHA C210 STA $C0A1 8D A1 C0 C213 RTS 60 C214 NOP EA C215 GETCHA C215 STA (BASL),Y 91 28 C217 LDA $C0A0 AD A0 C0 C21A RTS object code: A9 C2 85 37 85 39 A9 10 85 36 A9 15 85 38 60 EA 8D A1 C0 60 EA 91 28 AD A0 C0 60 */