grafX2/src/impdraw_loader.h
2019-12-23 22:13:12 +01:00

66 lines
3.0 KiB
C

/* vim:expandtab:ts=2 sw=2:
*/
/**
* Amstrad CPC Loader for overscan picture.
* Locomotive BASIC + Z80 Code.
* @author Ast/iMP4CT
* @see https://amstradplus.forumforever.com/t462-iMPdraw-v2-0.htm?start=45
*/
static const unsigned char impdraw_loader[] = {
0x0e, 0x00, 0x0a, 0x00, 0x01, 0xc0, 0x20, 0x69, // starts at &0170
0x4d, 0x50, 0x20, 0x76, 0x32, 0x00, 0x0d, 0x00, // 10 ' iMP v2
0x14, 0x00, 0xad, 0x20, 0x0e, 0x01, 0x83, 0x1c, // 20 MODE 0:CALL &1ad
0xad, 0x01, 0x00, 0x00, 0x00, // &0184 : token 0x0e = 0, 0x0f = 1, 0x10 = 2
0x01, 0x30, 0x02, 0x32, 0x06, 0x22, 0x07, 0x23, // From &018d CRTC registers
0x0c, 0x0d, 0xd0, 0x00, 0x00, 0x3f,
0xff, 0x00, 0xff, 0x77, 0xb3, 0x51, 0xa8, 0xd4, // From &019b CPC Plus ASIC unlocking sequence
0x62, 0x39, 0x9c, 0x46, 0x2b, 0x15, 0x8a, 0xcd,
0xee,
0x00, // &01ac = CPC PLUS flag (0=CPC old, 1=CPC+)
0xf3, // 01ad di
0x21, 0x8d, 0x01, // 01ae ld hl,&018d
0x3e, 0x06, // 01b1 ld a,&06
0x01, 0xbe, 0xbd, // 01b3 ld bc,BDBE
0xed, 0xa3, // 01b6 outi ; first decrements b <---+
0x41, // 01b8 ld b,c |
0xed, 0xa3, // 01b9 outi |
0x3d, // 01bb dec a |
0x20, 0xf8, // 01bc jz nz,01B6 ; loop ------------+
// load colors into gate array (from 7F00 ;)
0x01, 0x00, 0x7f, // 01be ld bc,7F00 ; Gate array
0x1e, 0x10, // 01c1 ld e,10
0x0a, // 01c3 ld a,(bc) <---+
0xed, 0x49, // 01c4 out (c),c ; select ink# |
0xed, 0x79, // 01c6 out (c),a ; set ink |
0x0c, // 01c8 inc c |
0x1d, // 01c9 dec e |
0x20, 0xf7, // 01ca jz nz,01C3 ; loop ---------+
0x3a, 0xac, 0x01, // 01cc ld a,01AC ; CPC PLUS flag
0xfe, 0x01, // 01cf cp 01
0x20, 0x22, // 01d1 jz nz,01F5 ; flag != 1 => skip CPC+
// CPC Plus ASIC unlock
0x21, 0x9b, 0x01, // 01d3 ld hl,019B
0x01, 0x11, 0xbc, // 01d6 ld bc,BC11
0x7e, // 01d9 ld a,(hl) <---+
0xed, 0x79, // 01da out (c),a |
0x2c, // 01dc inc l |
0x0d, // 01dd dec c |
0x20, 0xf9, // 01de jr nz,01D9 ; loop --+
// set CPC Plus colors
0x01, 0xb8, 0x7f, // 01e0 ld bc,7FB8
0xed, 0x49, // 01e3 out (c),c ; open ASIC I/O
0x21, 0x01, 0x08, // 01e5 ld hl,0801
0x11, 0x00, 0x64, // 01e8 ld de,6400
0x01, 0x20, 0x00, // 01eb ld bc,0020
0xed, 0xb0, // 01ee ldir ; copy bc bytes from (hl) to (de)
0x01, 0xa0, 0x7f, // 01f0 ld bc,7FA0
0xed, 0x49, // 01f3 out (c),c ; close ASIC I/O
0x21, 0xf9, 0xb7, // 01f5 ld hl,B7F9 ; SCR Event Block: Set Inks
0xcd, 0xdd, 0xbc, // 01f8 call BCDD ; remove event block for CRTC IRQ
0xfb, // 01fb ei
0xc3, 0x18, 0xbb, // 01fc jp BB18 ; Wait Keypress
0x00 // 01ff
};