Interesting video on TZXduino and tape speed

[Sparky]

I just watched this video and thought it to be worth mentioning it here. I always wondered about cassette tape speeds and how they work.
This one explains a lot though it uses the CPC as an example it is still applicable to the Speccy.

https://www.youtube.com/watch?v=MAIsOIwgJWA

[Ast A. Moore]

The OTLA for the Spectrum loader supports speeds of up to 19 KBaud using the standard sound input port. As for using alternative ports, the ZX Spectrum Codemasters CD Game Pack used the joystick port (although the loading speed was fairly low).

[patters]

Is there a way to get a Maxduino/Tzxduino to output OTLA encoded content?

[lister_of_smeg]

Is there a way to get a Maxduino/Tzxduino to output OTLA encoded content?

Yes, although the TZXDuino/MaxDuino firmware can't do it...

A while ago I wrote my own firmware for the TZXDuino as a proof of concept which could output TZX files created by OTLA, which comprise of a single ID15 (Direct Recording) block. I was able to successfully load a few test files on an Issue 6 48K, tape-in modded +2 and a +3.

The firmware was VERY basic and didn't interact with the display or the buttons, instead simply decoding and outputting from a hardcoded file on the SD card. It also only implemented a small subset of the block types from the TZX specs.

I never took it any further, but I've donated the code to Noel in the hope it may assist him with his project.

[patters]

I just had a look at OTLA and I can't figure out how to build it for macOS. There's no Makefile and no configure script. It's hosted on the now defunct Google Code, and hasn't been touched since 2008 apparently.

EDIT - looks like it's for Windows only.

[Ast A. Moore]

looks like it's for Windows only.

I seem to remember running it under Wine.

EDIT: Oh, yeah. It runs just fine: