NEW PREFIX /A2OSX.BUILD AUTO 4,1 *-------------------------------------- Z80.pPs .EQ pPs+0F000H Z80.pCode .EQ pCode+0F000H Z80.pData .EQ pData+0F000H Z80.pStack .EQ pStack+0F000H Z80.pLocal .EQ pLocal+0F000H *-------------------------------------- Z80.6502P.N .EQ %10000000 Z80.6502P.V .EQ %01000000 Z80.6502P.B .EQ %00010000 Z80.6502P.D .EQ %00001000 Z80.6502P.I .EQ %00000100 Z80.6502P.Z .EQ %00000010 Z80.6502P.C .EQ %00000001 *-------------------------------------- .OP Z80 .OR 0 *-------------------------------------- * First time entry point after reset * Called from Kernel.Init2 *-------------------------------------- Z80.Init ld SP,000FFH Init Stack to 000FFH ($10ff) ld A,0FFH Set Flag... ld Z80.6502A,A ...in 6502 A reg im 1 ei jr Z80.Exit *-------------------------------------- .BS 00038h-* *-------------------------------------- Z80.Irq push AF push BC push DE push HL push IX push IY ld (Z80.pStack),SP *-------------------------------------- Z80.Exit ld Z80.IOz,A exit to 6502, falling in main loop for next call *-------------------------------------- * Called from : * - CORE.PSExec : Z80.6502X = PS.INIT/PS.RUN/PS.DOEVENT/PS.QUIT * - CORE.PSExec : Resume * - SYSCALL Return * - LIBCALL Return * - *-------------------------------------- Z80.Enter ld A,(Z80.6502X) get 6502,X cp A,PS.RESUME jpz Z80.Resume ld L,A ld H,0 HL=offset in jump table ld DE,(Z80.pCode) DE=Code Base add DE,4 skip header add HL,DE HL=CodeBase+4+X ld A,(HL) get jmp lo at X inc HL ld H,(HL) get jmp hi at X+1 ld L,A call Z80.JumpHL ld Z80.6502A,A *-------------------------------------- Z80.Resume ld SP,(Z80.pStack) pop IY pop IX pop HL pop DE pop BC pop AF ei reti *-------------------------------------- *-------------------------------------- Z80.SYSCALL ld *-------------------------------------- Z80.LIBCALL *-------------------------------------- Z80.JumpHL jp (HL) *-------------------------------------- Z80.IOz .DA 0E100H Z80.6502A .BS 1 Z80.6502X .BS 1 Z80.6502Y .BS 1 Z80.6502P .BS 1 *-------------------------------------- MAN SAVE /A2OSX.SRC/SYS/KERNEL.S.Z80 LOAD /A2OSX.SRC/SYS/KERNEL.S ASM