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RC2024/10 - my entry

A while ago I made this MIDI module for RC2014: It works but a better design would have its own serial chip and port decoding.  As it is, it provides the MIDI interface and a clock signal for the second SIO2 serial port. This means that it requires a little setting up and will only work for RC2014s with an SIO2 (and port B not already used). My challenge to myself is to  learn how to connect a serial chip (probably 68B50 ACIA) to receive the incoming MIDI and to serialise outgoing MIDI design the module, including the port decoding write a library so that it can easily be used on any RC2014. Potential applications include a MIDI sequencer and using incoming MIDI to trigger notes on the AY or SID sound chips. Entering the Retro Challenge 2024 (aka RC2024/10)  has given me an incentive to get on with this! I'm happy to see several more entries in the RC2014 category, including another musical project.  Project logs: 1 Oct  68B50, ports, MIDI serial 4 Oct  remarked chips, prototyping
Recent posts

New MSX graphics / sound / joystick module for RC2014 / RCBus

I'm impressed at what Les has packed onto this standard-sized module. It contains an FPGA replacement for the TMS9918A, a YM/AY sound module and joystick interface.  The project is open-source and is here . In MSX terms this is the VDP (vidio display processor) and PSG (programmable sound generator), thus being an alternative for both the J B Langston TMS9918A video module and Ed Brindley's YM/AY sound module and adds two joystick ports to boot. All on a single module for RC2014 or compatible computers. There's no room for the d-sub joystick ports, so headers are provided so that these ribbon cables can be used.  This is a neat solution for those wishing to take advantage of Les' MSX8 system , which loads most MSX rom files along with a modified MSX BIOS from CP/M on a ROMWBW RC2014.  It is hard-wired to the MSX ports for the sound and video, so it won't be suitable for those wanting to run Colecovision ROMs, for example. I'm torn myself between the real TMS

Diagnosing and fixing a couple of sprite issues with my TMS9918A emulator

Recently I've been working on a small hardware enhancement for my TMSEMU board for RC2014 to allow it to be used with my MSX2014 and perhaps more importantly, with MSX ROMs running on the CP/M RC2014 .  Anyway, I've reduced the additional circuit to a single logic IC and couple of passives, so I'll be adding that to the TMSEMU board very soon. You can see the additional circuitry on a bit of proto board in this picture, and you can see the fantastic picture that the TMSEMU gives to my MSX2014 (and to any RC2014). However, this showed up a couple of problems that I hadn't been aware of with my TMS emulation, specifically with sprites. The first happens with the game 'The Goblin' (sorry for the reflection). The screen should be blank other than the decorative border at that point but many sprites are still showing. The second shot shows one of my favourite games, Keystone Kapers, you can see bits of sprites appearing in the top border. These problems may or may n

How to convert images for TMS9918A graphics on the RC2014

For me, graphics capability is essential for an 8-bit computer. My graphics chip of choice for the RC2014 is the very capable TMS9918A. It has 15 colours, sprites, several modes and a max resolution of 256x192. It makes arcade-style games possible, such as Tut-Tut above.  I enjoy simply displaying images and have a bunch on my CF card (my 'hard drive') and have written image viewer and slideshow apps to display them. Some useful links: Convert9918 Tutorial of Convert9918's settings Multipaint J B Langston's TMS9918A video module my own TMSEMU video module my respository of TMS9918A software, games and .s2/.sc3 images Image conversion I did dabble in writing my own utility to convert .png images but then settled on the Multipaint app which can open a png in a MSX 'screen 2', allow you to tidy it up with paint tools and save as a .sc2 file. (An sc2 file is little more than a video-memory dump and so it's easy to blast that back into vram to display the image.