Added CODE and DATA type headers, and using offsets for LDI and SVI. Not bothering with multitasking and context switching for now.
This commit is contained in:
Russell-S-Harper
parent
8576353b73
commit
99fc2c9feb
|
|
@ -25,9 +25,9 @@ Completed:
|
|||
|
||||
In progress:
|
||||
|
||||
* context switching for simple multitasking
|
||||
* a unit test suite to ensure each instruction is correct
|
||||
* a proof-of-concept application
|
||||
* “simple” multitasking?
|
||||
|
||||
The meat of the project:
|
||||
|
||||
|
|
|
|||
|
|
@ -11,7 +11,7 @@ page6.obj: rom.h macros.h globals.h page6.src
|
|||
xa -C -M page6.asm -l page6.lbl -o page6.obj
|
||||
|
||||
globals.h: common.obj
|
||||
grep -E -v '^(_|CMN_CD|CMN_DT|FN_FX)' common.lbl | sed -e 's/, 0, 0x0000//' -e 's/, / = /' -e 's/ 0x/ \x24/' > globals.h
|
||||
grep -E -v '^(_|CMN_CD|CMN_DT|FN_FX|CODE|DATA)' common.lbl | sed -e 's/, 0, 0x0000//' -e 's/, / = /' -e 's/ 0x/ \x24/' > globals.h
|
||||
|
||||
clean:
|
||||
rm -f globals.h page6.asm common.obj page6.obj common.lbl page6.lbl system.obj
|
||||
|
|
|
|||
|
|
@ -2,6 +2,7 @@
|
|||
#include "common.h"
|
||||
|
||||
; ROM code header
|
||||
.BYTE CODE
|
||||
.WORD CMN_CD, _END_CMN_CD - CMN_CD
|
||||
|
||||
; beginning of ROM code
|
||||
|
|
@ -976,14 +977,13 @@ _CPR .( ; CPR pq 0c pq Rp <- Rq - copy register
|
|||
|
||||
_INILS .( ; common initialization for LDI and SVI
|
||||
JSR _CPYI1 ; copy q to I1
|
||||
CLC ; shift to get an address
|
||||
ROR _I1+3
|
||||
ROR _I1+2
|
||||
ROR _I1+1
|
||||
CLC
|
||||
ROR _I1+3
|
||||
ROR _I1+2
|
||||
ROR _I1+1
|
||||
CLC ; add the allocated memory offset
|
||||
LDA _ARL
|
||||
ADC _I1+1
|
||||
STA _I1+1
|
||||
LDA _ARH
|
||||
ADC _I1+2
|
||||
STA _I1+2
|
||||
RTS
|
||||
.)
|
||||
|
||||
|
|
@ -1054,6 +1054,7 @@ _3 ORA _F
|
|||
_END_CMN_CD
|
||||
|
||||
; ROM data header
|
||||
.BYTE DATA
|
||||
.WORD CMN_DT, _END_CMN_DT - CMN_DT
|
||||
|
||||
; beginning of ROM data
|
||||
|
|
@ -1071,6 +1072,7 @@ MNS_1 .BYTE $00, $fc, $ff, $ff
|
|||
_END_CMN_DT
|
||||
|
||||
; 6502 addresses
|
||||
.BYTE DATA
|
||||
.WORD ADDR, 6
|
||||
|
||||
; 6502 NMI, Reset and IRQ
|
||||
|
|
|
|||
|
|
@ -46,9 +46,6 @@
|
|||
; SVI pq 0e pq (int(Rp)) <- Rq - save indirect via allocated memory offset
|
||||
; CMR pq 0f pq F <- Rp <=> Rq - compare registers
|
||||
|
||||
; 32 bytes in page zero for memory map allocation
|
||||
_MAP = _R0 - 256 / 8
|
||||
|
||||
; 40 bytes in page zero for common registers
|
||||
_R0 = $100 - 4 * (10 + 10)
|
||||
_R1 = _R0 + 4
|
||||
|
|
@ -69,8 +66,8 @@ _I3 = _I2 + 4
|
|||
_I4 = _I3 + 4
|
||||
_I5 = _I4 + 4
|
||||
_I6 = _I5 + 4 ; register I6 maintains common status
|
||||
_I7 = _I6 + 4 ; register I7 maintains locations of process and allocated memory
|
||||
_I8 = _I7 + 4 ; register I8 maintains process information for context switching
|
||||
_I7 = _I6 + 4 ; register I7 maintains locations of code and allocated memory
|
||||
_I8 = _I7 + 4 ; register I8 is reserved for future use, e.g. context switching
|
||||
_I9 = _I8 + 4 ; register I9 saves/restores processor status
|
||||
|
||||
; register I6 maintains common status
|
||||
|
|
@ -91,19 +88,15 @@ _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 locations of code and allocated real memory addresses
|
||||
; register I7 maintains locations of code and allocated memory
|
||||
_CRL = _I7 ; code low and high bytes
|
||||
_CRH = _CRL + 1
|
||||
_ARL = _CRH + 1 ; allocated low and high bytes
|
||||
_ARH = _ARL + 1
|
||||
_CR = _CRL ; code real memory address
|
||||
_AR = _ARL ; allocated real memory address
|
||||
_CR = _CRL ; code memory address
|
||||
_AR = _ARL ; allocated memory address
|
||||
|
||||
; register I8 maintains process information for context switching
|
||||
_PSO = _I8 ; offset to running processes table
|
||||
_PSF = _PSO + 1 ; initial running process status PPPCCCLF
|
||||
_PST = _PSF + 1 ; current process status
|
||||
_PSI = _PST + 1 ; process stack index to save/restore
|
||||
; register I8 is reserved for future use, e.g. context switching
|
||||
|
||||
; register I9 saves/restores processor status
|
||||
; (dd cc bb aa) aa: accumulator, bb: index X, cc: index Y, dd: processor status
|
||||
|
|
@ -116,31 +109,11 @@ _PS = _IDY + 1 ; saved processor status to restore
|
|||
|
||||
; using some of page two for register stack
|
||||
_RS = $200 ; register stack
|
||||
_RSS = _R0 ; register stack size
|
||||
_RSS = FN_FX - _RS ; register stack size
|
||||
|
||||
; for context switching, _R0 to _RS + _RSS - 1 needs to be saved and restored
|
||||
; this should comprise two pages or 512 bytes
|
||||
; system & user functions
|
||||
|
||||
; the following are common process table and system & user functions
|
||||
|
||||
; process information in the middle of page two
|
||||
_RP = _RS + _RSS ; running processes table
|
||||
_RPS = FN_FX - _RP ; running process table size
|
||||
|
||||
; process information indices
|
||||
_RPV_I = 0 ; 4 bytes virtual memory address
|
||||
_RPR_I = _RPV_I + 4 ; 2 bytes real memory address
|
||||
_RPS_I = _RPR_I + 2 ; 1 byte size in pages: code + allocated memory + context switching
|
||||
_RPF_I = _RPS_I + 1 ; 1 byte status PPPCCCLF: P priority / C counter / L loaded / F finished
|
||||
|
||||
; bits for status
|
||||
_S_L = 1 ; if program is loaded in memory
|
||||
_S_F = 2 ; if program is finished
|
||||
|
||||
_RPE = _RPF_I + 1 ; size of running process entry
|
||||
_RPL = _RPS / _RPE ; number of running processes limit
|
||||
|
||||
; last 32 bytes of page two
|
||||
; 32 bytes at the end of page two
|
||||
FN_FX = $300 - 2 * 16 ; list of system and user functions
|
||||
|
||||
; function constants
|
||||
|
|
@ -183,4 +156,8 @@ _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
|
||||
|
||||
; section identifiers
|
||||
CODE = %10101010 ; to indicate CODE section
|
||||
DATA = %01010101 ; to indicate DATA section
|
||||
|
||||
#endif /* __COMMON_H */
|
||||
|
|
|
|||
|
|
@ -78,7 +78,7 @@
|
|||
#define EXT(f) .BYTE _EXT_C + (f)
|
||||
|
||||
; header, begin and end of blocks
|
||||
#define HDR(a) .WORD a, _END_##a - a:* = * - 4:a .(
|
||||
#define HDR(t, a) .BYTE t:.WORD a, _END_##a - a:* = * - 5:a .(
|
||||
#define BGN(a) a .(
|
||||
#define END(a) .):_END_##a
|
||||
|
||||
|
|
|
|||
|
|
@ -4,12 +4,16 @@
|
|||
|
||||
* = $600
|
||||
|
||||
HDR(DEMO)
|
||||
HDR(CODE, DEMO)
|
||||
CMN
|
||||
SET(R0, 9.4662)
|
||||
SET(R1, 0)
|
||||
SVI(R1, R0)
|
||||
PSH(R0)
|
||||
BRS(FACTORIAL)
|
||||
POP(R4)
|
||||
SET(R5, 0)
|
||||
LDI(R6, R5)
|
||||
ESC
|
||||
BRK
|
||||
|
||||
|
|
@ -29,4 +33,9 @@ END(FACTORIAL)
|
|||
|
||||
END(DEMO)
|
||||
|
||||
SVD_T .BYTE 0, 0, 0, 0
|
||||
HDR(DATA, WORKING)
|
||||
|
||||
ONE .BYTE 0, 0, 0, 0
|
||||
TWO .BYTE 0, 0, 0, 0
|
||||
|
||||
END(WORKING)
|
||||
|
|
|
|||
|
|
@ -7,6 +7,7 @@
|
|||
#define _R8 0xd0
|
||||
#define _I0 0xd8
|
||||
#define _I6 0xf0
|
||||
#define _I7 0xf4
|
||||
#define _I8 0xf8
|
||||
|
||||
/* (dd cc bb aa) aa: index for register stack RS / ccbb: program counter PC / dd: flags F UONPZLGE */
|
||||
|
|
@ -16,6 +17,17 @@
|
|||
#define _F _PCH + 1 /* flags */
|
||||
#define _PC _PCL /* program counter */
|
||||
|
||||
/* register I7 maintains locations of code and allocated memory */
|
||||
#define _CRL _I7 /* code low and high bytes */
|
||||
#define _CRH _CRL + 1
|
||||
#define _ARL _CRH + 1 /* allocated low and high bytes */
|
||||
#define _ARH _ARL + 1
|
||||
#define _CR _CRL /* code memory address */
|
||||
#define _AR _ARL /* allocated memory address */
|
||||
|
||||
#define CODE 0xaa /* to indicate CODE section */
|
||||
#define DATA 0x55 /* to indicate DATA section */
|
||||
|
||||
uint8_t memory[65536];
|
||||
|
||||
uint8_t read6502(uint16_t address) {
|
||||
|
|
@ -48,22 +60,34 @@ void hook() {
|
|||
|
||||
int main() {
|
||||
|
||||
uint8_t header[4];
|
||||
uint8_t header[5];
|
||||
|
||||
while (fread(header, sizeof(header), 1, stdin))
|
||||
{
|
||||
uint16_t index = header[0] + (header[1] << 8);
|
||||
uint16_t length = header[2] + (header[3] << 8);
|
||||
uint8_t type = header[0];
|
||||
uint16_t index = header[1] + (header[2] << 8);
|
||||
uint16_t length = header[3] + (header[4] << 8);
|
||||
|
||||
printf("\n%04x %u\n", index, length);
|
||||
printf("\n%x %04x %u\n", type, index, length);
|
||||
|
||||
if (fread(memory + index, length, 1, stdin))
|
||||
{
|
||||
memory[_PCL] = header[0];
|
||||
memory[_PCH] = header[1];
|
||||
switch (type) {
|
||||
case CODE:
|
||||
memory[_CRL] = header[1];
|
||||
memory[_CRH] = header[2];
|
||||
break;
|
||||
case DATA:
|
||||
memory[_ARL] = header[1];
|
||||
memory[_ARH] = header[2];
|
||||
break;
|
||||
}
|
||||
}
|
||||
}
|
||||
|
||||
memory[_PCL] = memory[_CRL];
|
||||
memory[_PCH] = memory[_CRH];
|
||||
|
||||
hookexternal(hook);
|
||||
|
||||
reset6502();
|
||||
|
|
|
|||
Loading…
Reference in New Issue