Ecosyste.ms: Awesome
An open API service indexing awesome lists of open source software.
https://github.com/visrealm/vremu6502
6502/65C02 emulator library (C99)
https://github.com/visrealm/vremu6502
6502 6502-emulation 6510 65c02 65c02-emulation c c99 emulator r65c02 wdc65c02
Last synced: 3 days ago
JSON representation
6502/65C02 emulator library (C99)
- Host: GitHub
- URL: https://github.com/visrealm/vremu6502
- Owner: visrealm
- License: mit
- Created: 2022-01-22T07:01:35.000Z (over 2 years ago)
- Default Branch: main
- Last Pushed: 2024-06-05T14:06:11.000Z (4 months ago)
- Last Synced: 2024-09-24T21:19:36.413Z (3 days ago)
- Topics: 6502, 6502-emulation, 6510, 65c02, 65c02-emulation, c, c99, emulator, r65c02, wdc65c02
- Language: C
- Homepage:
- Size: 490 KB
- Stars: 41
- Watchers: 3
- Forks: 16
- Open Issues: 0
-
Metadata Files:
- Readme: README.md
- License: LICENSE
Awesome Lists containing this project
README
# vrEmu6502
6502/65C02 emulator written in standard C99 with no external dependencies.
Initially created for my [HBC-56 (6502 on a backplane) Emulator](https://github.com/visrealm/hbc-56)
Includes:
* Support for standard 6502/6510, 65C02, WDC65C02 and R65C02.
* Supports all unofficial ("illegal") 6502/6510 opcodes (Use model value `CPU_6502U`).
* Correct handling of Decimal mode.
* Accurate instruction timing.
* All WDC and Rockwell-specific 65C02 instructions.
* User-supplied I/O callbacks.
* IRQ and NMI signals.
* Multiple CPU instances.
* Instruction disassembler.
* Test runner.
## Test suite
Includes a test program which was designed to run [Klaus Dormann's 6502 tests](https://github.com/Klaus2m5/6502_65C02_functional_tests).
Passes all tests:
* 6502_functional_test (all models)
* 6502_decimal_test (with valid and invalid bcd) (6502)
* 65C02_decimal_test (with valid and invalid bcd) (all 65C02 models)
* 65C02_extended_opcodes_test (Standard 65C02)
* W65C02_extended_opcodes_test (WDC65C02)
* R65C02_extended_opcodes_test (R65C02)
See the [test](test) directory or more details.
## Building
vrEmu6502 uses the CMake build system
#### Checkout repository:
```
git clone https://github.com/visrealm/vrEmu6502.git
cd vrEmu6502
```
#### Setup build:
```
mkdir build
cd build
cmake ..
```
#### Build
```
cmake --build .
```
Windows: Optionally, open the generated solution file
#### Run tests
```
ctest
```
Windows: Optionally, build the ALL_TESTS project in the generated solution file
## Quick start
```C
#include "vrEmu6502.h"
uint8_t ram[0x8000];
uint8_t rom[0x8000];
uint8_t My6502MemoryReadFunction(uint16_t addr, bool isDbg)
{
if (addr < 0x8000)
{
return ram[addr];
}
return rom[addr & 0x7fff];
}
void My6502MemoryWriteFunction(uint16_t addr, uint8_t val)
{
if (addr < 0x8000)
{
ram[addr] = val;
}
}
/* fill rom with something that makes sense here */
/* create a new WDC 65C02. */
VrEmu6502 *my6502 = vrEmu6502New(CPU_W65C02, My6502MemoryReadFunction, My6502MemoryWriteFunction);
if (my6502)
{
/* if you want to interrupt the CPU, get a handle to its IRQ "pin" */
vrEmu6502Interrupt *irq = vrEmu6502Int(my6502);
/* reset the cpu (technically don't need to do this as vrEmu6502New does reset it) */
vrEmu6502Reset(my6502);
while (1)
{
/* call me once for each clock cycle (eg. 1,000,000 times per second for a 1MHz clock) */
vrEmu6502Tick(my6502);
/* interrupt it? */
if (myHardwareWantsAttention)
{
*irq = IntRequested;
/* at some point, the hardware will be happy and it will need to release the interrupt */
}
}
vrEmu6502Destroy(my6502);
my6502 = NULL;
}
```
See [HBC-56](https://github.com/visrealm/hbc-56) for real-life example usage.
## License
This code is licensed under the [MIT](https://opensource.org/licenses/MIT "MIT") license