A bit of context
As far as I remember I always wanted to have a led display of the Amstrad CPC signals, like on the old skool Altair / Imsai / educational kits... you know, Xmas tree vibes!
But obviously these LEDs would blink too fast to see anything. The CPC had to be slowed down. Since the Wait signal is used by the Gatearray, I had to find another way. The DMA mode was my second choice, although I often read that it was difficult to use on CPC...

As things advanced I really had fun with DMA and it appeared that this little project finally had some usefulness !

So I decided to design a tool based on my experiments, with these guidelines in mind:

• The gear should look Ooold SKooooool
• No CPU, only LOGIC components of the CPC era (also because I had quite a lot of these TTL LS chips in my drawers)
• Have fun!

Tool Features
Beyond its Educational interest, AMSTair offers you a way to Hack your games in real time, Debug code / ports, Diagnostic faulty CPC and much more...

• Display CPC control lines via LEDs
• Slow down your Amstrad at chosen speed
• Freeze mode with step by step functionality : Step on each Clock, DMA access, CPU instruction, port read, port write, Memory access
• Select the IO port you want to scan
• Show address lines in binary and data lines in hexadecimal
• Output the selected data to SOUND (Really?!)
• Digiblaster compatible mode
• DMA read or write in each cpu modes : fast, slow, paused
• DMA can r/w Memory and IO ports
• Selection of DMA address and data via switchs
• Selection of Port or Memory address to intercept via switchs
• Force DMA for dead z80
• CPC or external power supply
• Reset Amstrad

This tool is compatible with the Amstrad CPC 464, 646, 6128, 464 Plus and 6128 Plus

Ah oui... c'est à la fois incroyable, utile, une idée originale, pratique pour le déveloveppement, etc.