eeeck/tyvm
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add trap registrer

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This commit is contained in:
Erick
2022-02-04 23:44:17 +01:00
parent 7b6eb71618
commit 982ec371c8
1 changed files with 66 additions and 7 deletions
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tyvm.c
+66 -7
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@@ -22,8 +22,8 @@
/* sys libraries */
#include <sys/time.h>
#include <sys/types.h>
#include <termios.h>
#include <mman.h>
#include <sys/termios.h>
#include <sys/mman.h>
#endif
#define TRUE 1
@@ -89,12 +89,12 @@ uint16_t sign_extend(uint16_t n, int bit_count) {
/* Flag update function
Every time a value is written to a register the flag will be updated */
void update_flags(uint16_t r) {
if (reg[r] == 0) reg[RG_COND] = FL_Z;
else if (reg[r] >> 15) reg[RG_COND] = FL_N;
if(reg[r] == 0) reg[RG_COND] = FL_Z;
else if(reg[r] >> 15) reg[RG_COND] = FL_N;
else reg[RG_COND] = FL_P;
}
/* main loop */
int main(int argc, const char* argv[]) {
if(argc < 2) {
@@ -206,7 +206,7 @@ int main(int argc, const char* argv[]) {
uint16_t BaseR = (instr >> 6) & 0x7;
uint16_t offset6 = sign_extend(instr & 0x1FF, 6);
reg[sr] = mem_read(offset6 + BaseR);
reg[sr] = mem_read(offset6 + BaseR); //TODO: check if reg[] is needed
update_flags(dr);
@@ -256,7 +256,66 @@ int main(int argc, const char* argv[]) {
break;
case OP_TRAP:
//{TRAP};
enum {
TRAP_GETC = 0x20, // get charcter from keyboard
TRAP_OUT = 0x21, // output a character
TRAP_PUTS = 0x22, // output a word string
TRAP_IN = 0x23, // get charcter from keyboard and echo to terminal
TRAP_PUTSP = 0x24, // output a byte string
TRAP_HALT = 0x25 // halt program
};
switch(instr & 0xFF) {
case TRAP_GETC:
reg[RG_000] = (uint16_t)getchar();
break;
case TRAP_OUT:
putc((char)reg[RG_000], stdout);
fflush(stdout);
break;
case TRAP_PUTS:
uint16_t* stringPnt = memory + reg[RG_000];
uint16_t* c;
while (*c) {
putc((char)*c, stdout);
++c;
}
fflush(stdout);
break;
case TRAP_IN:
char c = getchar();
putc(c, stdout);
fflush(stdout);
reg[RG_000] = (uint16_t)c;
update_flags(RG_000);
break;
case TRAP_PUTSP:
uint16_t* ch = memory + reg[RG_000];
while (*ch) {
char char1 = (*ch) & 0xFF;
putc(char1, stdout);
char char2 = (*ch) >> 8;
if (char2) putc(char2, stdout);
++ch;
}
fflush(stdout);
break;
case TRAP_HALT:
puts("HALT");
fflush(stdout);
running = FALSE;
break;
default:
abort();
}
break;
case OP_RES: // reserved
case OP_RTI: // unused