collapseos/blk/450
Virgil Dupras 25a35cf28e Move 8086 boot code from B800 to B440
That slims down blkfs a lot.
2020-09-21 20:09:42 -04:00

16 lines
522 B
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lblchkPS BSET ( CX -> expected size )
AX PS_ADDR MOVxI, AX SP SUBxx, 2 SUBAXI, ( CALL adjust )
AX CX CMPxx,
IFNC, ( we're good ) RETn, THEN,
( underflow ) DI 0x06 MOVxm, JMPs, lblexec @ RPCs,
PC 3 - ORG @ 1+ ! ( main )
DX POPx, ( boot drive no ) 0x03 DL MOVmr,
SP PS_ADDR MOVxI, BP RS_ADDR MOVxI,
DI 0x08 MOVxm, ( LATEST )
( HERE begins at CURRENT )
SYSVARS 0x4 ( HERE ) + DI MOVmx,
SYSVARS 0x2 ( CURRENT ) + DI MOVmx,
DI 0x04 ( BOOT ) MOVxm,
JMPn, lblexec @ RPCn, ( execute )