collapseos/arch/z80/sms/xcomp.fs
Virgil Dupras 2b8524d11e sms: CPORT_CTL is write-only!
why did I think that I could read from it?
2020-11-08 08:43:24 -05:00

42 lines
1.0 KiB
Forth

( 8K of onboard RAM )
0xdd00 CONSTANT RS_ADDR
( Memory register at the end of RAM. Must not overwrite )
0xddca CONSTANT PS_ADDR
RS_ADDR 0x80 - CONSTANT SYSVARS
0xc000 CONSTANT HERESTART
SYSVARS 0x70 + CONSTANT VDP_MEM
0xbf CONSTANT VDP_CTLPORT
0xbe CONSTANT VDP_DATAPORT
32 CONSTANT VDP_COLS
24 CONSTANT VDP_ROWS
SYSVARS 0x72 + CONSTANT CPORT_MEM
0x3f CONSTANT CPORT_CTL
0xdc CONSTANT CPORT_D1
0xdd CONSTANT CPORT_D2
SYSVARS 0x73 + CONSTANT PAD_MEM
5 LOAD ( z80 assembler )
: ZFILL, ( u ) 0 DO 0 A, LOOP ;
262 LOAD ( xcomp )
524 LOAD ( font compiler )
282 LOAD ( boot.z80.decl )
270 LOAD ( xcomp overrides )
DI, 0x100 JP, 0x62 ZFILL, ( 0x66 )
RETN, 0x98 ZFILL, ( 0x100 )
( All set, carry on! )
CURRENT @ XCURRENT !
0x100 BIN( !
283 335 LOADR ( boot.z80 )
353 LOAD ( xcomp core low )
CREATE ~FNT CPFNT7x7
603 608 LOADR ( VDP )
625 626 LOADR ( SMS ports )
612 617 LOADR ( PAD )
390 LOAD ( xcomp core high )
(entry) _
( Update LATEST )
PC ORG @ 8 + !
," VDP$ PAD$ (im1) " EOT,
ORG @ 0x100 - 256 /MOD 2 PC! 2 PC!
H@ 256 /MOD 2 PC! 2 PC!