Logo Logo
 

BMC64 | BMC128 | BMVIC20 | BMPLUS4

BMC64-Lite (Now included in V3.0+)

BMC64-Lite is a variant of BMC64 for the Rasbperry Pi Zero. The device is not as powerful as the Pi 2/3 so the emulator won't be able to keep up with some demanding demos. However, most games should work. If you are looking for better performance, you should consider a Pi2/3 and use BMC64 For Rasbperry Pi 2/3 

The differences between BMC64-Lite and BMC64 are:

  • Slightly degraded sound quality.

    BMC64-lite uses an older, less CPU intensive version of ReSid and is set to 33Khz sampling rate instead 44.1Khz found in BMC64.

  • Slightly longer boot time.

    BMC64-Lite boots in about 7-8 seconds as opposed BMC64's 4.1 seconds.

  • Snapshots saved from BMC64 will not load into BMC64-Lite (and vice versa).

    They are not compatible and the emulator will simply hang.

  • Drive emulation sounds have been removed.
  • 60Hz NTSC configuration is not recommended.

What's the performance of BMC64-Lite vs. BMC64?

BMC64-Lite performs 'well enough' on the Pi Zero for most games. However, you will run into some demos that exceed the frame deadline at 50Hz, especially when expanded multi-colored sprites are heavily used. In those cases, BMC64-Lite audio/video will stutter. Feel free to report your success/failures on lemon64.com. I've tried demos COMALAND and Star Wars and they do stutter at a couple of spots. However, games like Sam's Journey, Uridium, Galencia and many others appear to work without issue. The bottom line is, performance is quite acceptable in most cases but your mileage may vary.

Will this work on a Rasbperry Pi 1?

I don't recommend BMC64-Lite for the Pi 1. The device's 700Mhz clock is not enough to meet the CPU + video + sound load of some games/demos. However, I recognize some people might want to dig up their old devices sitting at the bottom of desk drawers and put them to use. This build will run on a RPi 1 but the only way to get decent performance would be to overclock the device. If you are not comfortable with overclocking your Pi 1, the solution is to get a Pi2 or Pi3. Otherwise, read on...

These are the overclock settings I've tested on my Pi 1 Model B that give decent performance:

   arm_freq=1000
   core_freq=350
   sdram_freq=500
   sdram_schmoo=0x02000020
   over_voltage=6
   sdram_over_voltage=6
   temp_limit=75
Make sure you have a good power supply capable of supplying at least 750mA.

* NOTE: If you are swapping the same SD card with both BMC64 and BMC64-Lite builds between Pi 2/3/0 and Pi 1, remember to comment out these settings for Pi0/2/3!

Overclocking seems to be a bit of an art form. There is some good information at : https://github.com/RetroPie/RetroPie-Setup/wiki/Overclocking. If you see odd behavior (like random resets or freezes), it is likely due to the overclock settings. I don't intend on supporting any issues reported for the Pi 1 for this reason.

** Remember to modify config.txt for Rasbperry Pi 1 if you decide to go ahead and overclock it. **

Most games/demos appear to run fine with these settings and they are fairly safe but each Pi is different. What works for my Pi may not for yours. You may have to experiment.

NOTE: I ONLY TESTED Pi 1 Model B w/ 512Mb RAM. Since I don't have a Pi 1 Model A+, I can't test it. The memory is configured for 512MB in this build so I don't know how the Pi 1 Model A+ will deal with that.

Again, these additional settings are for the Pi 1 only. There is no reason to overclock any other Pi model.


© 2019 Randy Rossi (randyrossi at gmail dot com) - All rights reserved (2019/01/30)