1
0
mirror of https://github.com/hsoft/collapseos.git synced 2024-11-26 10:38:07 +11:00

Compare commits

...

2 Commits

Author SHA1 Message Date
Virgil Dupras
2b7abf802f pcat: begin porting forth
I'm not sure yet where I'm going, but I'm not going to build the
8086 port from the ground up like I did with the z80, that is,
making is sustain itself and eventually merge its forth code with
core words. That would be too much work which would then be thrown
out (all those words I'll initially have to implement in asm which
are already implemented in Forth).

What I *think* I can do is build a mirror version of z80 boot code
and cross-compile it from the z80. This means it has to follow z80
stable ABI.

Nope, I'm not sure where I'm going...
2020-06-13 21:37:54 -04:00
Virgil Dupras
1a467efae1 pcat: use a far jump to boot into the OS
Unless I misunderstood, this is supposed to set CS. This would make
all SREG have the same value. This allows us to remove BIN( offset
from os.bin.

I've tried booting to offset 0, but it didn't seem to work. Let's
settle for 0x8000. 512kb of system RAM is way more than we need
anyways.
2020-06-13 20:06:51 -04:00
6 changed files with 26 additions and 15 deletions

View File

@ -4,3 +4,4 @@
;
: PC H@ ORG @ - BIN( @ + ;
: A, C, ;
: A,, SPLITB A, A, ;

View File

@ -1,12 +1,13 @@
: OP1 CREATE C, DOES> C@ A, ;
0xac OP1 LODSB, 0xfa OP1 CLI, 0xfb OP1 STI,
0xf4 OP1 HLT, 0xfc OP1 CLD, 0xfd OP1 STD,
( no argument, jumps with abs addrs are special )
( no argument, jumps with relative addrs are special )
0xeb OP1 JMPs, 0xe9 OP1 JMPn, 0x74 OP1 JZ,
: MOVri, SWAP 0xb0 OR A, A, ;
: MOVxi, SWAP 0xb8 OR A, SPLITB A, A, ;
: MOVsx, 0x8e A, SWAP 3 LSHIFT OR 0xc0 OR A, ;
: INT, 0xcd A, A, ;
: JMPr, 0xff A, 7 AND 0xe0 OR A, ;
: JMPf, ( seg off ) 0xea A, SPLITB A, A, SPLITB A, A, ;
: OPrr CREATE C, DOES> C@ A, 3 LSHIFT OR 0xc0 OR A, ;
0x31 OPrr XORxx, 0x08 OPrr ORrr,

View File

@ -2,9 +2,9 @@ H@ ORG ! 0x7c00 BIN( ! ( BIOS loads boot bin at 0x7c00 )
JMPs, L1 FWRs ( start )
ORG @ 0x25 + HERE ! ( bypass BPB )
L1 FSET ( start )
CLI, CLD, AX AX XORxx, DS AX MOVsx, ES AX MOVsx,
CLI, CLD, AX 0x800 MOVxi, DS AX MOVsx, ES AX MOVsx,
SS AX MOVsx, SP 0xffff MOVxi, STI,
AH 2 MOVri, DX 0 MOVxi, CH 0 MOVri, CL 2 MOVri, AL 1 MOVri,
BX 0x8000 MOVxi, 0x13 INT, ( read 2nd sector of boot floppy )
BX JMPr,
BX 0 MOVxi, 0x13 INT, ( read 2nd sector of boot floppy )
0x800 0 JMPf,
ORG @ 0x1fe + HERE ! 0x55 A, 0xaa A,

26
blk/812
View File

@ -1,10 +1,16 @@
H@ ORG ! 0x8000 BIN( !
JMPs, L1 FWRs ( start )
L2 ( msg ) BSET ," Hello World!" 0 A,
L1 FSET ( start )
SI L2 @ ( msg ) MOVxi, AH 0x0e MOVri, ( print char )
L1 BSET ( loop ) LODSB, AL AL ORrr, ( end of str? )
JZ, L2 FWRs ( next ) 0x10 INT, ( print char )
JMPs, L1 ( loop ) BWR
L2 FSET ( next ) AH 0 MOVri, 0x16 INT, ( read kbd )
AH 0x0e MOVri, 0x10 INT, ( spit read char ) HLT, ( done )
( Registers. SP -> PSP DX -> RSP CX -> IP )
H@ ORG !
JMPn, 0 A,, ( 00, main ) JMPn, 0 A,, ( 03, find )
0 A,, ( 06, unused ) 0 A,, ( 08, LATEST )
0 A, ( 0a, unused ) JMPn, 0 A,, ( 0b, cellWord )
JMPn, 0 A,, ( 0e compiledWord ) JMPn, 0 A,, ( 11, pushRS )
JMPn, 0 A,, ( 14, popRS )
JMPn, 0 A,, ( 17, nativeWord )
JMPn, 0 A,, ( 1a, next ) JMPn, 0 A,, ( 1d, chkPS )
0 A, 0 A, ( 20, numberWord ) 0 A, 0 A, ( 22, litWord )
0 A, 0 A, ( 24, addrWord ) 0 A, 0 A, ( 26, unused )
0 A, 0 A,, ( unused )
JMPn, 0 A,, ( 2b, doesWord ) 0 A, 0 A, ( 2e, unused )
0 A, 0 A,, ( unused )
JMPn, 0 A,, ( 33, execute ) 0 A, 0 A, ( unused )
0 A, 0 A,, ( unused )

3
blk/813 Normal file
View File

@ -0,0 +1,3 @@
PC 3 - ORG @ 1+ ! ( main )
AH 0x0e MOVri, ( print char ) AL 'X' MOVri, 0x10 INT,
HLT,

View File

@ -1,4 +1,4 @@
750 LOAD
812 LOAD
812 813 LOADR
ORG @ 256 /MOD 2 PC! 2 PC!
H@ 256 /MOD 2 PC! 2 PC!