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Implemented basic arduino vm.

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Updated LDA to be M[D] = RX + IMM
Updated STA to be RD = M[RX + IMM]
Updated SYS to be RD = SYSCALL(RX, IMM)
Added error callback to VM, replaced printfs with callback.

Added syscalls.
This commit is contained in:
Sam Stevens
2018-10-22 00:01:47 +01:00
parent 6abacd4c1d
commit 600be14336
5 changed files with 377 additions and 113 deletions
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55
arduino/arduino.ino
View File

@@ -14,6 +14,11 @@ See the License for the specific language governing permissions and
limitations under the License.
*/
/**
* Example Programs
* Hello World: 0x311833021210c0323401411412103416e4203406d400000048656c6c6f20576f726c640a
*/
#include "vm.h"
#include "console.h"
@@ -21,15 +26,57 @@ VM vm;
Console console(&vm);
void setup() {
// put your setup code here, to run once:
vm_reset(&vm);
Serial.begin(9600);
vm.error = vm_print_error;
vm.syscall = vm_syscall;
Serial.begin(1200);
console.setSerial(&Serial);
}
void loop() {
// put your main code here, to run repeatedly:
console.loop(&Serial);
console.loop();
}
void vm_print_error(uint8_t err) {
Serial.print("\n");
switch(err) {
case VM_ERR_MISALIGN:
Serial.println("Halted. PC misaligned.");
break;
case VM_ERR_UNKNOWN_OP:
Serial.println("Halted. Unknown instruction. (this should never happen)");
break;
case VM_ERR_OUT_OF_BOUNDS:
Serial.println("Halted. Operation out of bounds.");
break;
default:
Serial.println("Halted. Unknown Error.");
break;
}
}
uint8_t vm_syscall(VM* vm, uint8_t callno, uint8_t imm) {
// Serial.print("SYSCALL 0x");
// Serial.print(callno, HEX);
// Serial.print(". IMM=");
// Serial.print(imm);
// Serial.println("");
switch(callno) {
case 0:
delay(1<<imm);
break;
case 1:
delayMicroseconds(1<<imm);
break;
case 2:
if (imm < VM_REG_SIZE) {
Serial.print((char)vm->R[imm]);
}
break;
default:
return 0;
}
return 0;
}

352
arduino/console.cpp
View File

@@ -16,102 +16,34 @@ limitations under the License.
#include <Arduino.h>
#include <HardwareSerial.h>
#include <errno.h>
#include "console.h"
Console::Console(VM* _vm) {
this->state = CONSOLE_NONE;
this->vm = _vm;
this->inputBuffer = new String("");
this->serial = NULL;
}
void Console::loop(HardwareSerial * serial) {
int i;
char d;
int Console::hexToDec(String str) {
errno = 0;
long int result = strtol(str.c_str(), NULL, 16);
if (errno != 0 || result < 0) {
return -1;
}
return (int)result;
}
switch(this->state) {
case CONSOLE_NONE:
serial->println("Press Enter to activate console.");
this->state = CONSOLE_OFF;
break;
case CONSOLE_OFF:
if(serial->available()) {
if (serial->read() == 10) {
serial->println("Console active. Type ? for help.");
this->state = CONSOLE_ACTIVATE;
void Console::setSerial(HardwareSerial *serial) {
this->serial = serial;
}
}
break;
case CONSOLE_ACTIVATE:
serial->print("> ");
this->state = CONSOLE_ACTIVE;
break;
case CONSOLE_ACTIVE:
if(serial->available()) {
while((d = (char)serial->read()) != -1) {
if (d == 27) {
//escape, deactivate console
this->inputBuffer = new String("");
serial->println("Console deactivated.");
this->state = CONSOLE_NONE;
} else if (d == '\n') {
//Finished input
serial->print("\n");
if (this->inputBuffer->equals("?")) {
serial->print(F(
"Commands\n"
"? | this help\n"
"q | deactivate console\n"
"r | run until halted\n"
"s | step one instruction\n"
"e | examine and update memory\n"
"v | show vm status\n"
"rst | reset PC and registers\n"
"clr | reset and clear memory\n"
));
serial->print("> ");
} else if (this->inputBuffer->equals("q")) {
serial->println("Console deactivated.");
this->state = CONSOLE_NONE;
} else if (this->inputBuffer->equals("r")) {
this->state = CONSOLE_RUN;
} else if (this->inputBuffer->equals("s")) {
this->state = CONSOLE_STEP;
} else if (this->inputBuffer->equals("e")) {
this->state = CONSOLE_EXAMINE;
} else if (this->inputBuffer->equals("v")) {
this->state = CONSOLE_VIEW;
} else if (this->inputBuffer->equals("rst")) {
this->state = CONSOLE_RESET;
} else if (this->inputBuffer->equals("clr")) {
this->state = CONSOLE_CLEAR;
} else {
serial->println("Unknown command. Type ? for help.");
serial->print("> ");
}
this->inputBuffer = new String("");
} else if (isAlphaNumeric(d) || isPunct(d) || isSpace(d)) {
//Append input to buffer
this->inputBuffer->concat(d);
serial->print(d);
}
}
}
break;
case CONSOLE_RUN:
break;
case CONSOLE_STEP:
break;
case CONSOLE_EXAMINE:
break;
case CONSOLE_VIEW:
//PC
serial->print( "PC ");
serial->print(this->vm->PC, HEX);
serial->print("\n");
//Registers
serial->print( "R ");
for(i = 0; i < VM_REG_SIZE; i++) {
void Console::printRegisters(bool header) {
if (header) {
serial->println(" 0 1 2 3 4 5 6 7 8 9 A B C D E F");
}
for(short i = 0; i < VM_REG_SIZE; i++) {
if (this->vm->R[i] < 0x10) {
serial->print("0");
}
@@ -119,10 +51,24 @@ void Console::loop(HardwareSerial * serial) {
serial->print(" ");
}
serial->print("\n");
}
//Memory
void Console::printMemory(uint16_t from, uint16_t to) {
uint16_t i = from;
serial->println(" 0 1 2 3 4 5 6 7 8 9 A B C D E F");
for(i = 0; i < VM_MEM_SIZE; i++) {
if (from > 0 && from % 16 != 0) {
i = from - (from % 16);
serial->print("0x");
if (i < 0x10) {
serial->print("0");
}
serial->print(i, HEX);
serial->print(" ");
for(; i < from; i++) {
serial->print(" ");
}
}
for(i = from; i <= to && i < VM_MEM_SIZE; i++) {
if (i % 16 == 0) {
if (i > 0) {
serial->print("\n");
@@ -145,8 +91,61 @@ void Console::loop(HardwareSerial * serial) {
serial->print(" ");
}
serial->print("\n");
}
void Console::loop() {
HardwareSerial * serial = this->serial;
int i;
switch(this->state) {
case CONSOLE_NONE:
serial->println("Press Enter to activate console.");
this->state = CONSOLE_OFF;
break;
case CONSOLE_OFF:
if(serial->available()) {
if (serial->read() == 10) {
serial->println("Console active. Type ? for help.");
this->state = CONSOLE_ACTIVATE;
}
}
break;
case CONSOLE_ACTIVATE:
serial->print("> ");
this->state = CONSOLE_ACTIVE;
break;
case CONSOLE_ACTIVE:
this->stateActive();
break;
case CONSOLE_RUN:
if(this->vm->halted == false) {
vm_step(this->vm);
} else {
serial->print("VM Halted. PC=0x");
serial->print(this->vm->PC);
serial->println(". Registers:");
this->printRegisters(true);
this->state = CONSOLE_ACTIVATE;
}
break;
case CONSOLE_STEP:
if (this->vm->halted == false) {
vm_step(this->vm);
if (this->vm->halted == true) {
serial->print("VM Halted. ");
}
serial->print("PC=0x");
serial->print(this->vm->PC);
serial->println(". Registers:");
this->printRegisters(true);
}
this->state = CONSOLE_ACTIVATE;
break;
case CONSOLE_EXAMINE:
this->stateExamine();
break;
case CONSOLE_VIEW:
this->stateView();
break;
case CONSOLE_RESET:
vm_reset(this->vm);
@@ -164,3 +163,182 @@ void Console::loop(HardwareSerial * serial) {
}
}
void Console::stateActive() {
HardwareSerial * serial = this->serial;
char d;
if(serial->available()) {
while((d = (char)serial->read()) != -1) {
if (d == 27) {
//escape, deactivate console
this->inputBuffer = new String("");
serial->println("Console deactivated.");
this->state = CONSOLE_NONE;
} else if (d == '\n') {
//Finished input
serial->print("\n");
if (this->inputBuffer->equals("?")) {
serial->print(F(
"Commands\n"
"? | This help\n"
"q | Deactivate console\n"
"r | Run until halted\n"
"s | Step one instruction\n"
"e | Examine/update\n"
"v | Show vm status\n"
"rst | Reset PC and registers\n"
"clr | Reset and clear memory\n"
));
serial->print("> ");
} else if (this->inputBuffer->equals("q")) {
serial->println("Console deactivated.");
this->state = CONSOLE_NONE;
} else if (this->inputBuffer->equals("r")) {
this->vm->halted = false;
this->state = CONSOLE_RUN;
} else if (this->inputBuffer->equals("s")) {
this->vm->halted = false;
this->state = CONSOLE_STEP;
} else if (this->inputBuffer->equals("e")) {
serial->println("Type q to return to console. Type ? for help.");
serial->print("E> ");
this->state = CONSOLE_EXAMINE;
} else if (this->inputBuffer->equals("v")) {
this->state = CONSOLE_VIEW;
} else if (this->inputBuffer->equals("rst")) {
this->state = CONSOLE_RESET;
} else if (this->inputBuffer->equals("clr")) {
this->state = CONSOLE_CLEAR;
} else {
serial->println("Unknown command. Type ? for help.");
serial->print("> ");
}
this->inputBuffer = new String("");
} else if (isAlphaNumeric(d) || isPunct(d) || isSpace(d)) {
//Append input to buffer
this->inputBuffer->concat(d);
serial->print(d);
}
}//while serial read
}//if serial available
}//Console::stateActive
void Console::stateView() {
int i;
//PC
serial->print( "PC ");
serial->print(this->vm->PC, HEX);
serial->print("\n");
//Registers
serial->print( "R ");
this->printRegisters(false);
//Memory
this->printMemory(0, VM_MEM_SIZE-1);
this->state = CONSOLE_ACTIVATE;
}//Console::stateView
void Console::stateExamine() {
char d;
int location, value;
if(serial->available()) {
while((d = (char)serial->read()) != -1) {
if (d == 27) {
//escape, go back to console
this->inputBuffer = new String("");
this->state = CONSOLE_ACTIVATE;
} else if (d == '\n') {
//Finished input
serial->print("\n");
this->inputBuffer->toUpperCase();
if (this->inputBuffer->equals("?")) {
serial->print(F(
"Commands\n"
"? | This help\n"
"q | Return to console\n"
"PC | Show program counter\n"
"PC=yyyy | Set program counter\n"
"R | Show register contents\n"
"Rx=yy | Update register\n"
"Myy,zz | Show zz bytes of memory starting at xx\n"
"Myy=zz | Update memory at yy with zz, may repeat zz for subsequent bytes\n"
"x = 0-F, yy/zz = 00-FF\n"
));
} else if (this->inputBuffer->equals("Q")) {
this->state = CONSOLE_ACTIVATE;
} else if (this->inputBuffer->equals("PC")) {
serial->println(this->vm->PC, HEX);
} else if (this->inputBuffer->startsWith("PC") && this->inputBuffer->indexOf("=") != -1) {
value = this->hexToDec(this->inputBuffer->substring(this->inputBuffer->indexOf("=")+1));
if (value >= 0 && value < VM_MEM_SIZE) {
this->vm->PC = value;
} else {
serial->println("Invalid value");
}
} else if (this->inputBuffer->equals("R")) {
this->printRegisters(true);
} else if (this->inputBuffer->startsWith("R") && this->inputBuffer->indexOf("=") != -1) {
location = this->hexToDec(this->inputBuffer->substring(1, this->inputBuffer->indexOf("=")));
value = this->hexToDec(this->inputBuffer->substring(this->inputBuffer->indexOf("=")+1));
if (location >= 0 && location < VM_REG_SIZE) {
if (value >= 0 && value <= 255) {
this->vm->R[location] = (uint8_t)value;
} else {
serial->println("Invalid value");
}
} else {
serial->println("Invalid register");
}
} else if (this->inputBuffer->startsWith("M") && this->inputBuffer->indexOf(",") != -1) {
location = this->hexToDec(this->inputBuffer->substring(1, this->inputBuffer->indexOf(",")));
value = this->hexToDec(this->inputBuffer->substring(this->inputBuffer->indexOf(",")+1));
if (value + location >= VM_MEM_SIZE) {
value = VM_MEM_SIZE-1;
}
if (location >= 0 && location < VM_MEM_SIZE) {
if (value > 0) {
this->printMemory(location, location + value);
} else {
serial->println("Invalid value");
}
} else {
serial->println("Invalid start location");
}
} else if (this->inputBuffer->startsWith("M") && this->inputBuffer->indexOf("=") != -1) {
location = this->hexToDec(this->inputBuffer->substring(1, this->inputBuffer->indexOf("=")));
String x = this->inputBuffer->substring(this->inputBuffer->indexOf("=")+1);
if (x.length() % 2 != 0) {
serial->println("Invalid data. 2 characters per byte required");
} else {
for(int i = 0; i < x.length(); i += 2) {
value = this->hexToDec(x.substring(i, i+2));
if (value >= 0 && value <= 255) {
this->vm->M[location++] = value;
} else {
serial->println(i);
serial->println(x.substring(i, i+2));
serial->println(value);
serial->println("Invalid data.");
break;
}
}
}
} else {
serial->println("Unknown command.");
serial->print("E> ");
}
if (this->state == CONSOLE_EXAMINE) {
serial->print("E> ");
}
this->inputBuffer = new String("");
} else if (isAlphaNumeric(d) || isPunct(d) || isSpace(d)) {
//Append input to buffer
this->inputBuffer->concat(d);
serial->print(d);
}
}//while serial read
}//if serial available
}//Console::stateExamine

13
arduino/console.h
View File

@@ -38,9 +38,20 @@ class Console {
ConsoleState state;
VM *vm;
String *inputBuffer;
HardwareSerial *serial;
int hexToDec(String);
void printRegisters(bool);
void printMemory(uint16_t, uint16_t);
void stateActive();
void stateView();
void stateExamine();
public:
Console (VM*);
void loop(HardwareSerial*);
void setSerial(HardwareSerial*);
void loop();
};
#endif //UVM_CONSOLE_H

45
arduino/vm.c
View File

@@ -16,7 +16,6 @@ limitations under the License.
#include <stdlib.h>
#include <string.h>
#include <stdio.h>
#include "vm.h"
VM *new_vm() {
@@ -94,7 +93,9 @@ void vm_step(VM *vm) {
uint8_t PC = vm->PC;
if (PC % 2 != 0) {
fprintf(stderr, "Halted. PC not aligned.\n");
if (vm->error != NULL) {
vm->error(VM_ERR_MISALIGN);
}
vm->halted = true;
return;
}
@@ -112,12 +113,32 @@ void vm_step(VM *vm) {
uint16_t temp16 = 0;
switch (inst.op) {
case OP_LDA:
vm_decode_Q(&inst, raw);
d = vm->M[inst.imm];
vm_decode_T(&inst, raw);
x = vm_get_r(vm, inst.rx);
temp16 = x;
temp16 += inst.imm;
if (temp16 < VM_MEM_SIZE) {
d = vm->M[temp16];
} else {
if (vm->error != NULL) {
vm->error(VM_ERR_OUT_OF_BOUNDS);
}
vm->halted = true;
}
break;
case OP_STA:
vm_decode_Q(&inst, raw);
vm->M[inst.imm] = vm_get_r(vm, inst.rd);
vm_decode_T(&inst, raw);
x = vm_get_r(vm, inst.rx);
temp16 = vm_get_r(vm, inst.rd);
temp16 += inst.imm;
if (temp16 < VM_MEM_SIZE) {
vm->M[temp16] = x;
} else {
if (vm->error != NULL) {
vm->error(VM_ERR_OUT_OF_BOUNDS);
}
vm->halted = true;
}
break;
case OP_LDI:
vm_decode_Q(&inst, raw);
@@ -172,11 +193,12 @@ void vm_step(VM *vm) {
d = x >> vm_get_r(vm, inst.imm);
break;
case OP_SYS:
vm_decode_Q(&inst, raw);
vm_decode_T(&inst, raw);
x = vm_get_r(vm, inst.rx);
if (vm->syscall != NULL) {
d = vm->syscall(vm, inst.imm);
d = vm->syscall(vm, x, inst.imm);
} else {
printf("SYSCALL #%d\n", inst.imm);
d = 0;
}
break;
case OP_JMP:
@@ -200,11 +222,12 @@ void vm_step(VM *vm) {
}
break;
case OP_HLT:
printf("Halted at 0x%04X\n", PC);
vm->halted = true;
break;
default:
printf("Unknown Instruction at 0x%04X: 0x%hhX\n", PC, inst.op);
if (vm->error != NULL) {
vm->error(VM_ERR_UNKNOWN_OP);
}
vm->halted = true;
break;
}

7
arduino/vm.h
View File

@@ -40,6 +40,10 @@ limitations under the License.
#define OP_JEQ 0xe
#define OP_JLT 0xf
#define VM_ERR_MISALIGN 0x1
#define VM_ERR_UNKNOWN_OP 0x2
#define VM_ERR_OUT_OF_BOUNDS 0x3
#ifdef __cplusplus
extern "C" {
#endif
@@ -59,7 +63,8 @@ struct VM_t {
uint8_t M[VM_MEM_SIZE];
uint8_t carry;
bool halted;
uint8_t (*syscall)(struct VM_t* vm, uint8_t callno);
uint8_t (*syscall)(struct VM_t* vm, uint8_t callno, uint8_t imm);
void (*error)(uint8_t err);
};
typedef struct VM_t VM;