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Adding I9 for context switching.

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Russell-S-Harper 2018-10-30 03:38:42 -04:00
parent 6ffe70daec
commit 9045e06439
2 changed files with 19 additions and 16 deletions
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25
common/common.h
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@ -47,7 +47,7 @@
; CMR pq 0f pq F <- Rp <=> Rq - compare registers
; 40 bytes in page zero for common registers
_R0 = $100 - 4 * (10 + 9)
_R0 = $100 - 4 * (10 + 10)
_R1 = _R0 + 4
_R2 = _R1 + 4
_R3 = _R2 + 4
@ -58,7 +58,7 @@ _R7 = _R6 + 4
_R8 = _R7 + 4
_R9 = _R8 + 4
; 36 bytes in page zero for internal registers
; 40 bytes in page zero for internal registers
_I0 = _R9 + 4 ; workspace
_I1 = _I0 + 4
_I2 = _I1 + 4
@ -66,8 +66,9 @@ _I3 = _I2 + 4
_I4 = _I3 + 4
_I5 = _I4 + 4
_I6 = _I5 + 4 ; register I6 maintains common status
_I7 = _I6 + 4 ; register I7 maintains process information for context switching
_I8 = _I7 + 4 ; register I8 saves/restores processor status
_I7 = _I6 + 4 ; register I7 maintains locations of process and allocated memory
_I8 = _I7 + 4 ; register I8 maintains process information for context switching
_I9 = _I8 + 4 ; register I9 saves/restores processor status
; register I6 maintains common status
; (dd cc bb aa) aa: index for register stack RS / ccbb: program counter PC / dd: flags F UONPZLGE
@ -87,15 +88,17 @@ _F_N = 32 ; if Rr < 0.0 (after TST)
_F_O = 64 ; if overflow (after arithmetic operations)
_F_U = 128 ; if underflow (after arithmetic operations)
; register I7 maintains process information for context switching
_PST = _I7 ; current process status
; register I7 maintains locations of process and allocated memory
; register I8 maintains process information for context switching
_PST = _I8 ; current process status
_PSI = _PST + 1 ; process stack index to save/restore
_PD0 = _PSI + 1 ; two bytes for process
_PD0 = _PSI + 1 ; pending
_PD1 = _PD0 + 1
; register I8 saves/restores processor status
; register I9 saves/restores processor status
; (dd cc bb aa) aa: accumulator, bb: index X, cc: index Y, dd: processor status
_ACC = _I8 ; saved accumulator to restore
_ACC = _I9 ; saved accumulator to restore
_IDX = _ACC + 1 ; saved index X to restore
_IDY = _IDX + 1 ; saved index Y to restore
_PS = _IDY + 1 ; saved processor status to restore
@ -152,7 +155,7 @@ _EXT_C = $f0
; common constants
_MSK_O = %11000000 ; mask for overflow
_MSK_R = %00111100 ; mask for registers
_MSK_T = (_F_Z + _F_P + _F_N)^$ff ; mask for TST
_MSK_C = (_F_E + _F_G + _F_L)^$ff ; mask for CMP
_MSK_T = (_F_Z + _F_P + _F_N) ^ $ff ; mask for TST
_MSK_C = (_F_E + _F_G + _F_L) ^ $ff ; mask for CMP
#endif /* __COMMON_H */

10
emulator/main.c
View File

@ -3,11 +3,11 @@
#include "emulator.h"
/* Register I6 maintains common status */
#define _R0 0xb4
#define _R8 0xd4
#define _I0 0xdc
#define _I6 0xf4
#define _I8 0xfc
#define _R0 0xb0
#define _R8 0xd0
#define _I0 0xd8
#define _I6 0xf0
#define _I8 0xf8
/* (dd cc bb aa) aa: index for register stack RS / ccbb: program counter PC / dd: flags F UONPZLGE */
#define _RSI _I6 /* register stack index */