🇲🇩 BYTE: Part 15 (It works!) [TCE скачать в хорошем качестве

🇲🇩 BYTE: Part 15 (It works!) [TCE

This is a clone of a British computer, built in Moldova using Soviet & East German parts and running a Czechoslovak firmware. After a long hiatus (since Jan 2024) from working on these ZX Spectrum clones from post-Soviet Moldova, I thought I'd have another crack ... a little wiser after 21 months of additional tinkering. I'd earlier had no luck getting any of these "Red BYTE" machines using the КА1515ХМ1-216 БМК (or Basic Matrix Crystal, the Soviet's Super ULA) working. It's a pretty simple design, not much there to go wrong ... or replace if it does go wrong: the БМК, the ROM, the CPU, the eight DRAM chips and some additional logic for video & tape handling. Of course, the lack of decoupling capacitors didn't occur to me - only a few months ago I saw how much they can improve a machine's stability (another post-Soviet Speccy clone). However this one is actually working with just a few large electrolytics for decoupling ... maybe took a while to acclimatise to the Aussie weather. The video was a bit unstable but improved a little with the addition of some additional decoupling capacitors. I could not get anything to load (WAV file played back on my Mac mini using Audacity) so will need to investigate some more - the TAPE IN (TI) on the БМК is getting quite a noisy signal (idle high?) from the К561ЛН2 CMOS hex inverter (pretty standard method on Soviet clones) ... perhaps cleaning that up will help? Possibly replace with a CD4069? I'm not sure what the БМК's specification/requirement for the signal is. 00:15 ... Brief overview of the Moldovan BYTEs 03:45 ... Current video output 04:40 ... Additional decoupling capacitors 06:15 ... Improved video output 08:15 ... Test program(me) 09:15 ... Expansion port (2.5mm pitch) 10:30 ... Tape input 13:10 ... Oscilloscope trace of tape input signal 17:00 ... Replace tape input hex inverter? 17:15 ... Channel thanks & outro 15/Jan/2024 ... 1501 subs 21/Oct/2025 ... 3304 subs -------------------------------- Check out my Patreon for regular blog-type updates between videos - there is a free membership tier and two paid tiers (US$2 and US$5). There is also a one-week trial for the paid tiers so if you don't think it's worth it, then cancel ... no hard feelings ... I appreciate any support, even if it's just subscribing to my YouTube channel!   / thecluelessengineer   -------------------------------- Music by Karl Casey @ White Bat Audio https://karlcasey.bandcamp.com    / @whitebataudio