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Programmer (Finally!)

A project log for Z80 overpowered computer

I am building a computer with a 4MHz Z80, 32KiB EEPROM, 32KiB RAM, IDE interface and UART.

dylan-brophyDylan Brophy 04/28/2017 at 00:562 Comments

For a looooong time I have only been able to find absurdly expensive programmers, none at a reasonable price. It SUCKED. Some on ebay were even 1000+ dollars! Ridiculous! Finally I found one for 42$ on ebay here. It came in the mail today and I finally can properly program my Z80 computer.

Why I bought a programmer and didn't build one

I tried programming with my arduino mega. Not only was it tedious and difficult, it hardly ever worked at all. It was a mess. I must have programmed it almost properly once because when I read it with my new TL866CS one of my OSes were there, but in the wrong spot. I think like 32 bytes from the start of the EEPROM, instead of at byte 0.

Is the programmer working well?

Yes! Although it's cheap compared to other programmers it works very well and is easy for me to use. It also programs sooooo many devices. And I got a program to run on my Z80 board!

Problems with my z80 computer

I got a program to run. Barely. I can't remember the address for the debug parallel output, so I just sent 0x55 to every address to debug it. That worked, but I don't know which address that was. The UART wont work (Now that I can test it), and no LED will light up on the peripheral board for my guess at the IDE address. So its pretty much an unusable system (for now). I would like to have an ATX motherboard layout anyways...

Possible solution?

I was coming up with some ideas for a full on Z80 ATX motherboard a few months ago to solve another problem : these boards don't fit in any case! Oh, and an ATX board would allow compatibility with more modern cases, allowing case USB connections and a bit of a surprise to the unsuspecting user. What I was thinking then was how expensive that would be and how much I would never want to pay for making the boards. I discovered Tindie around then, and that's why I wanted to start selling my NGT20: to get into the market so that later I could build my Z80 stuff without loosing money, but rather gaining it. I just don't want to exhaust my bank account, ya know?


So, I really want to make a Z80 ATX motherboard. Without SATA and PCI and DDR-whatever RAM, but just compatible with the case, power supply, and an IDE hard drive/disk drive. If I get a floppy controller I will support floppy drives too.


Anyways, would anyone buy a Z80 ATX motherboard? I know I want one.

Discussions

Samuel A. Falvo II wrote 04/29/2017 at 20:31 point

I'd be interested in learning how to interface an ATX power supply to a project, more precisely.  For my needs, an ATX board would be huge, ideal for an expansion backplane.  I'd be interested in learning from such a project for those reasons.

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Dylan Brophy wrote 04/29/2017 at 22:01 point

I have worked with ATX connectors and got good control of the PSU with little more than a transistor, some wires, breadboard, and hacking the connector.  the PSU can be turned on with just a wire connecting two of the wires.... I forget which wires though.  I think its the green wire to the black wire.  There is actually good info around the internet for the topic too.  When I make the ATX board I will have to put up schematics.

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