This is a fork of randyrossi/bmc64 with two primary goals:
- VICE 3.9 - upgrade from VICE 3.3 to VICE 3.9 (released 2024-12-24), gaining the binary remote monitor protocol, ethernet/TFE emulation, and six years of emulation improvements.
- Raspberry Pi Zero 2W - primary test target is the Pi Zero 2W (BCM2710A1, quad-core Cortex-A53). Uses the Pi 3 code path.
C64 only. C128, VIC20, Plus/4, and PET are out of scope for this fork.
Fully working on Pi Zero 2W and Pi 3:
- C64 boots to READY screen
- Display - NTSC, 720p@60Hz HDMI
- Audio - HDMI, 6581 SID (reSID, Fast Resampling)
- GPIO keyboard PCB (gpio_config=1) and USB keyboard
- Positional keymap (
rpi_pos.vkm) as default - Cartridge loading (CRT, 8K, 16K, Ultimax)
- Disk and tape loading
- SwiftLink/ACIA virtual modem - Hayes AT commands, DNS, TCP BBS
- TFE ethernet (CS8900A) menu toggle
- SMSC951x (LAN9514) onboard Ethernet - ping, TFTP, TCP confirmed
- TFTP server on port 69 - upload/download files to SD card over the network
DHCP - IP assigned automatically on boot. Check Prefs → Network Info in the menu for the assigned address. To get a stable address, reserve the Pi's MAC in your router.
CNetInitTask in kernel.cpp calls CNetSubSystem::Initialize() with no static IP, which starts CDHCPClient internally and polls for a lease for up to 30 seconds. If no lease is granted, networking is silently skipped.
TFTP (SD card must be inserted; replace IP with the one shown in Network Info):
# Download a file from the Pi:
curl -o localfile.ini tftp://<pi-ip>/vice.ini
# Upload a file to the Pi:
curl --upload-file myfile.d64 tftp://<pi-ip>/disks/C64/myfile.d64SwiftLink virtual modem - enable Acia1Enable=1 in vice.ini:
ATZ → OK
ATDT host:port → TCP connect, responds CONNECT 38400
ATH → disconnect
Test BBS: ATDT bbs.retrocampus.com:6510
# Packages
sudo apt install gcc-arm-none-eabi build-essential automake autoconf libtool \
pkg-config autoconf-archive autotools-dev xa65
# Environment (add to ~/.bashrc or set before building)
export ARM_HOME=/usr
export PATH=$PATH:$ARM_HOME/bin
export ARM_VERSION=14.2.1
export PREFIX=arm-none-eabi-./clean_all.sh # required before first build
./make_all.sh pizero2w
./make_machines.sh pizero2wOutput kernel: kernel8-32.img (Pi 3 / Pi Zero 2W).
Copy kernel8-32.img to the SD card root as both kernel8-32.img and kernel8-32.img.c64.
| Board arg | Kernel filename | Hardware |
|---|---|---|
pizero2w |
kernel8-32.img |
Pi Zero 2W, Pi 3 |
pi4 |
kernel7l.img |
Pi 4 (CRT shader off) |
/
├── config.txt arm_64bit=0, gpu_mem=128
├── cmdline.txt fast=true machine_timing=ntsc-hdmi scaling_params=... audio_out=hdmi
├── vice.ini SidModel=0 SidStereo=0 Acia1Enable=1 KeymapIndex=1
├── kernel8-32.img boot kernel
├── kernel8-32-safe.img known-good backup kernel (see Safe Boot below)
├── C64/
│ ├── kernal
│ ├── basic
│ ├── chargen
│ ├── d1541II
│ ├── rpi_pos.vkm
│ └── rpi_maxi_pos.vkm
├── DRIVES/
│ └── (drive ROMs)
├── disks/
│ └── C64/ .d64, .g64, etc.
├── tapes/
│ └── C64/ .tap, .t64
├── carts/
│ └── C64/ .crt, .bin
└── snapshots/
└── C64/
File browser looks in /disks/C64, /carts/C64, /tapes/C64 by default (configurable via "Files Location Convention" in the Prefs menu - the alternative is /C64/disks, /C64/carts, etc.).
A backup kernel slot (kernel8-32-safe.img) provides hardware recovery from a bad kernel push without SD card removal.
Normal push via bmc_sync_to_pi.sh --kernel kernel8-32.img:
- Downloads the current
kernel8-32.imgfrom the Pi and saves it askernel8-32-safe.img - Uploads the new kernel as
kernel8-32.img
Recovery: hold the joystick fire button (either port, GPIO23 or GPIO19) while powering on. The kernel detects this before any emulation starts, copies kernel8-32-safe.img over kernel8-32.img, and reboots into the good kernel.
Manual recovery (if Pi won't boot at all): insert SD card into host, run:
cp /media/$USER/BMC64/kernel8-32-safe.img /media/$USER/BMC64/kernel8-32.imgcmdline.txt:
fast=true machine_timing=ntsc-hdmi scaling_params=384,240,1152,720 audio_out=hdmi
vice.ini (important settings for this fork):
MachineVideoStandard=1 ; NTSC - PAL-N causes audio drift/freeze
SidModel=0 ; 6581
SidStereo=0
Acia1Enable=1 ; SwiftLink virtual modem
KeymapIndex=1 ; positional keymap
KeymapUserPosFile="rpi_maxi_pos.vkm"
- No hot-plug - all USB devices must be connected before power-on.
- C64 only - other machine types are not built or supported in this fork.
- Pi 5 not supported - requires AArch64 and a full display/audio rewrite.
- USB gamepad support is limited; not all gamepads will work.
- F12 - open/close menu
- ESC / RUNSTOP - exit menu
- Commodore Key + F7 - alternate menu toggle (real keyboard)
| Usage | Mapping |
|---|---|
| USB keyboard | Positional (rpi_pos.vkm) |
| GPIO PCB | Positional |
| TheC64 Maxi | rpi_maxi_pos.vkm |
| Config | Description |
|---|---|
| 1 | Menu nav buttons + real joysticks |
| 2 | Real keyboard + real joysticks (PCB) |
| 3 | Waveshare Game HAT |
| 4 | Userport outputs + joysticks (dangerous - see below) |
| 5 | Custom defined |
Set via gpio_config=N in settings.txt (0-indexed: Config 2 = gpio_config=1).
Config 4 warning: capable of driving GPIO pins as 3.3V outputs. Never use with the keyboard PCB attached - direct pin-to-pin shorts will damage the GPIO. Requires enable_gpio_outputs=true in cmdline.txt to unlock from the menu.
Scaling and timing work the same as upstream BMC64 - see the upstream README for full detail on custom HDMI modes, integer scaling, DPI, and the CRT shader. Key points for this fork:
- NTSC (
machine_timing=ntsc-hdmi) is the tested/recommended mode. - CRT shader is automatically disabled on Pi 4+ (
circle_get_model() > 3). scaling_params=384,240,1152,720gives 3x integer scaling at 720p.
- ReSID, Fast Resampling, 6581 model.
audio_out=hdmiincmdline.txtis required - auto-detection misses HDMI on Pi Zero 2W.- A wall-clock rate limiter in
ViceSound::AddChunkprevents the GPU audio buffer from filling when VICE runs slightly faster than real-time (~0.1% on Pi Zero 2W).
For pre-compiled images, changelog, and full documentation for the multi-machine upstream build:
https://github.com/randyrossi/bmc64
https://accentual.com/bmc64
-e
