Agon Light C Programming - An Introduction

Instead of bashing away in BASIC, it's possible to do some coding in C on the Agon Light. Let's find out how in this introduction to an ongoing series where I figure out the Agon hardware and work on a game. I have no idea what game I want to make, and I'm not entirely sure how to achieve some of the necessary functions, but it'll be fun figuring it out and I hope you come along for the ride!
The first thing we need is a C compiler so that we're not stranded bashing code in BASIC, or getting lost and confused in raw assembly. There isn't an official C compiler, but Paul Cawte on Github has created a modification called AgDev for the unofficial C compiler toolchain for the Texas Instruments TI-84+ range of calculators, which have the same eZ80 CPU as the Agon Light.
I've written a post elsewhere on my site explaining how to set it up, and in this video show some of the things I've been working on. My aim is to develop some sort of game for the Agon Light using C, rather than BASIC.
Links:
Blog Post: ncot.uk/agon-l...
Github Repo: github.com/nco...
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Bill Bertram, CC BY-SA 2.5 creativecommon..., via Wikimedia Commons
Video by Pavel Danilyuk: www.pexels.com...

[@arronshutt]

"Or I'll give up and never mention it again..." made me laugh quite a bit. I've been interested in the Agon Light for a while, just trying not to get distracted from the two other major projects that I'm currently working on in my own time first! :)

[@The8bitNoob]

The agon has Vi binary already on the sdcard that comes with the emulator. it's in the mos folder i believe. edit: and welcome to the Agon party 😁.

[@Enos666]

I hope you keep at this, I'm tempted to pick one up to have a play around with.

[@assifmirza130]

Just finding this video. Really well put together. It exactly describes my workflow. I am loving being able to use a capable host to write and compile C (AgDev also) and have a short compile test cycle on the emulator before ever going near the hardware and sdcards. Looking forward to see what you create. PS chest infections suck. I know. Hope you feel better soon.

[@PhilHowlett]

Your video is perfect timing for me. I'm waiting for my Agon light to turn up in the mail so I'm setting up my own development environment. I'm curious to learn why you went down the CE C/C++ path rather than the z88dk path for the C compiler. I've just setup my environment for z88dk (compiled my hello.c file and can run it in the emulator).

[@TheClassicsCoder]

For me, the main reason was the more modern C-Compiler in CE and the missing graphics support which I found easier to add in the CE toolchain. Normally I'm also on Z88DK fo the Speccy stuff.

[@nickthesoulboy]

Looking forward to the next one!

[@lorensims4846]

I'm surprised it has a C compiler. The closest thing I had on my Atari 800 (with 48K) was Deep Blue C from the Atari Programmer Exchange. It was based on "small C" and didn't support structures or unions along with a lot of other features. Most annoying to me, the Atari keyboard didn't include braces so we had to us $( and $) instead.

[@jumhig]

Nice video! But why not mention the default/original C development environment for eZ80 , namely Zilog ZIDE 2. This is what I use for Agon Light dev, it's Windows only but that's not a problem for me. Would love to see more videos on Agon C programming, specifically how to upload bitmaps and manage sprites, which has a few gotchas. Also MOS functions, audio, keyboard / joystick input etc. I also have Agon C libraries for the graphical and audio functions, and the key up/down map.

[@ncot_tech]

To be honest the only time I looked at the Zilog C compiler was to see some #defines for the UART port. It is used for MOS though I discovered.

[@jumhig]

I see there is also a new "AgDev" C compiler for Agon too.

[@greenfrogcoding]

Great video 👍

[@mr_noodler]

Is there a C API for the Agon Light 2? I can’t find it anywhere

[@ncot_tech]

Not exactly. The AgDev toolchain is the closest we have, combined with the console8 documentation available here agonconsole8.github.io/agon-docs/ Once you understand how the VDP is controlled by literally printing text to the screen with special control codes, the BBC Basic examples are fairly straight forward to understand. My Github repo contains some useful code if you have a dig around in it, specifically the functions for writing 8 and 16 bit values to the VDP.