jake/SplitBit-Emulator
1
0
Fork 0
Code Issues Pull Requests Actions Packages Projects Releases Wiki Activity

CALL and RET instructions.

Browse Source 
Changed PSHP and POPP into CALL and RET, streamlining their use for subroutine calls.
Updated Assembler and Emulator.
New demonstration programs.
This commit is contained in:
Anachronaut
2024-10-27 19:18:54 -04:00
committed by GitHub
parent 78f827e9dc
commit 992e44ca12
7 changed files with 152 additions and 54 deletions
Download Patch File Download Diff File Expand all files Collapse all files
Source/Assembler/Assembler.c
+4 -1
View File
@@ -71,11 +71,14 @@ void assemblerCleanup(intermediateElement *intermediateArray, int arraySize, cha
}
// Free the intermediateArray itself.
free(intermediateArray);
// Free the list of included files.
freeIncludeList();
// Free the list of labels.
freeLabelList();
// Free the output file name.
// Free the output file name
free(outputFileName);
}
Source/Assembler/assembly.c
+6 -6
View File
@@ -27,6 +27,8 @@ Instruction instruction_set[] = {
{0x11, "BRQ"},
{0x12, "BRA"},
{0x13, "BRB"},
{0x14, "CALL"},
{0x15, "RET"},
// Register Operations:
{0x20, "RSTA"},
{0x21, "RSTB"},
@@ -42,12 +44,10 @@ Instruction instruction_set[] = {
{0x30, "PSHQ"},
{0x31, "PSHA"},
{0x32, "PSHB"},
{0x33, "PSHP"},
{0x34, "PSHD"},
{0x35, "POPA"},
{0x36, "POPB"},
{0x37, "POPP"},
{0x38, "POPD"},
{0x33, "PSHD"},
{0x34, "POPA"},
{0x35, "POPB"},
{0x36, "POPD"},
// Data Operations:
{0x40, "INCD"},
{0x41, "DECD"},
Source/Assembler/secondPass.c
+2 -2
View File
@@ -112,9 +112,9 @@ void populateOutputBuffers(intermediateElement *intermediateArray, int arraySize
Program[(*programCount)++] = intermediateArray[i].byteValue;
// Check if it's a branch instruction.
if ((intermediateArray[i].byteValue & 0xF0) == 0x10) {
if (((intermediateArray[i].byteValue & 0xF0) == 0x10) && (intermediateArray[i].byteValue != 0x15)){
if (intermediateArray[i + 1].type != LABEL) {
fprintf(stderr, "Error: Branch without label.\n");
fprintf(stderr, RED "Error: Branch without label.\n" RESET);
printf("File: %s at line %d.\n", intermediateArray[i].fileName, intermediateArray[i].lineNumber);
exit(1);
}
Source/Emulator/cpu.c
+22 -19
View File
@@ -114,6 +114,24 @@ uint8_t executeOperation(uint8_t Instruction, CPURegisters *cpu) {
cpu->ProgramCounter+=2;
}
break;
case 0x14:
// CALL - Push the Program Counter to the Stack, and perform an immediate branch.
// Order, low byte, high byte
cpu->Data[cpu->StackPointer] = cpu->ProgramCounter & 0xFF;
cpu->StackPointer--;
cpu->Data[cpu->StackPointer] = (cpu->ProgramCounter >> 8) & 0xFF;
cpu->StackPointer--;
genericBranch(cpu);
break;
case 0x15:
// RET - Return from subroutine, restore the Program Counter from the Stack.
// POPP - Pop Data to the Program Counter
cpu->StackPointer++;
cpu->ProgramCounter = (uint16_t)cpu->Data[cpu->StackPointer] << 8;
cpu->StackPointer++;
cpu->ProgramCounter = cpu->ProgramCounter | (uint16_t)cpu->Data[cpu->StackPointer];
cpu->ProgramCounter += 2; // Because it needs to skip over the address when it returns.
break;
//
// 2x - Register Operations:
//
@@ -177,15 +195,8 @@ uint8_t executeOperation(uint8_t Instruction, CPURegisters *cpu) {
cpu->Data[cpu->StackPointer] = cpu->B;
cpu->StackPointer--;
break;
case 0x33:
// PSHP - Push the Program Counter to the Stack.
// Order, low byte, high byte
cpu->Data[cpu->StackPointer] = cpu->ProgramCounter & 0xFF;
cpu->StackPointer--;
cpu->Data[cpu->StackPointer] = (cpu->ProgramCounter >> 8) & 0xFF;
cpu->StackPointer--;
break;
case 0x34:
case 0x33:
// PSHD - Push the Data Pointer to the Stack.
// Order, low byte, high byte
cpu->Data[cpu->StackPointer] = cpu->DataPointer & 0xFF;
@@ -193,26 +204,18 @@ uint8_t executeOperation(uint8_t Instruction, CPURegisters *cpu) {
cpu->Data[cpu->StackPointer] = (cpu->DataPointer >> 8) & 0xFF;
cpu->StackPointer--;
break;
case 0x35:
case 0x34:
// POPA - Pop Data to A.
cpu->StackPointer++;
cpu->A = cpu->Data[cpu->StackPointer];
break;
case 0x36:
case 0x35:
// POPB - Pop Data to B.
cpu->StackPointer++;
cpu->B = cpu->Data[cpu->StackPointer];
break;
case 0x37:
// POPP - Pop Data to the Program Counter
cpu->StackPointer++;
cpu->ProgramCounter = (uint16_t)cpu->Data[cpu->StackPointer] << 8;
cpu->StackPointer++;
cpu->ProgramCounter = cpu->ProgramCounter | (uint16_t)cpu->Data[cpu->StackPointer];
cpu->ProgramCounter += 3; // Because it needs to skip over the subsequent branch instruction on return.
break;
case 0x38:
case 0x36:
// POPD - Pop Data to the Data Pointer
cpu->StackPointer++;
cpu->DataPointer = (uint16_t)cpu->Data[cpu->StackPointer] << 8;