Sinclair ZX80 / ZX81 / Z88 Forums

I've built the executable as an ELF file, which is the default when using gcc. It appears RiscOS cannot load those file types without an ELF loader. I did try to use ELF2AIF, but that failed as I've dynamically linked in libraries. It looks like it all works for me, as I had installed an ELF loader....

Good news! After some more study of the ins and outs of RiscOS I've built and run sz81 2.3.12. Hi-res, sound, UDG and chroma all seem to be working at the right speed on a Pi4 running RiscOS. The build is also stable on a Pi2, but runs at less than full speed. Setting a higher frameskip helps. @zx4e...

I invested a few hours and tried to compile 2.3.12 on RiscOs using gcc 4 which can be installed on RiscOS. After some hacking, mainly due to RiscOs using . as a directory marker, I got it running to the K prompt. However, it did not last long on a Pi2 as it used all the CPU, starving the OS. I check...

Yes, Pico W is supported, although the emulator does not use the WiFi functionality. @Paul kindly gave me a Picomite board to work with, which had a Pico W installed. The boot time for the Pico H or W is very short, a few milliseconds. The time to get to the "K" prompt is governed by the emulated ZX...

Thanks for the tip - I tried again using a Pi2 and sz81 started ok. I then got ZX Galaxians running by doing the following: 1. Downloaded sz81, unzipped and copied using InfoZip 2. Ran up sz81, wrote and saved a 1 line program "fred" using SAVE "FRED" from the emulator. 3. Checked that I could load ...

Well, I'd never used RiscOS before today, so I thought I'd put it on an SDCard and give it a go on a Pi4. It installed ok, but the GUI is very different to what I'm used to :-) When I tried to run a pre-built version of sz81 from https://riscosports.co.uk/sz81.zip it seg faulted. Where did you get y...

I've now implemented support for the https://www.waveshare.com/wiki/Pico-ResTouch-LCD-2.8 . The screen resolution is 320x240. I've set the LCD up to receive RGB444, so that it can work at a sustained 60 Hz refresh rate. The refresh rate can also be configured for 50 Hz and 50.65 Hz. The Waveshare bo...

I've now measured the frame rate on my 240x240 LCD and it looks like 50Hz (but not 60Hz) should just be possible on a similar 320 by 240 display. I've decided to order a 2.8" 320 by 240 SPI display: https://www.waveshare.com/wiki/Pico-ResTouch-LCD-2.8 https://thepihut.com/products/2-8-touchscreen-di...

In think it could be made to work with small SPI displays such as the 2inch display (320x240). But some programming is required. One of the 2 cores of the Pi Pico is currently dedicated to generating the VGA or HDMI display. The challenge is to write to the small display fast enough over SPI using t...

I've been away on holiday for a while, but am back now and have updated the project Readme with the pictures - thank you :) Sound over hdmi is currently implemented on a separate branch - the hdmi_audio branch in Github. However, it does appear robust, and the uf2 files that support audio over hdmi ...