UK Vintage Radio Repair and Restoration Discussion Forum - View Single Post - Gemini 80-Bus System

NealCrook · 22nd Oct 2019, 7:17 pm

@cosmocat >> I was mulling the possibility of writing a program on the Nascom to read the disk image (in sections) over the serial port (from a PC) then using low level NASDOS routines to write the disk tracks so that when the PolyDos boot rom was installed the files would appear correctly. I was unsure if this approach would work though.

I'll start a new topic to discuss this

@JohnBHanson >>PS - If you can publish the source for your SD card patch via a PIO I would be interested.

I did not drive the SD card directly from the PIO (too much nascom-side software, particularly if any kind of file-system is needed) instead the PIO is connected to ports of an Arduino Nano, and the SDcard is attached to the Nano. This allows existing FAT library to be used for file-system-based storage, and allows a simple and high-level command interface between the NASCOM and the Arduino. Example program:

https://github.com/nealcrook/nascom/...ams/sd_wr1.asm

Neal.

22nd Oct 2019, 7:17 pm	#252
NealCrook Tetrode Join Date: May 2019 Location: Reading, Berkshire, UK. Posts: 51	Re: Gemini 80-Bus System @cosmocat >> I was mulling the possibility of writing a program on the Nascom to read the disk image (in sections) over the serial port (from a PC) then using low level NASDOS routines to write the disk tracks so that when the PolyDos boot rom was installed the files would appear correctly. I was unsure if this approach would work though. I'll start a new topic to discuss this @JohnBHanson >>PS - If you can publish the source for your SD card patch via a PIO I would be interested. I did not drive the SD card directly from the PIO (too much nascom-side software, particularly if any kind of file-system is needed) instead the PIO is connected to ports of an Arduino Nano, and the SDcard is attached to the Nano. This allows existing FAT library to be used for file-system-based storage, and allows a simple and high-level command interface between the NASCOM and the Arduino. Example program: https://github.com/nealcrook/nascom/...ams/sd_wr1.asm Neal.