No, it's very hectic. It's driving me crazy.

Off topic: I was chatting with a fellow Hungarian friend about ROM programming. I remembered him telling a story about how his dad built an Altair clone that he eventually painted purple. I asked him where did his dad purchase Intel-stuff? At the time the West embargoed export of high tech and ...

Just done the NOP test and indeed, as I moved the probe from A0 to A14 the frequency gradually decreased. Gave up trying to burn the EEPROM, the contraption is not working. At least I know that the SBC will work!

Good point, thanks!

The 28c64b is a 64 kilobit memory, 64K=(8K x 8 ), but it has only 8 kilobytes.
the 28c256, is a 256 kilobit chip, and it has 32 kilobytes of memory.

It seems I was trying to write a 32Kb image onto an 8Kb ROM. No wonder it didn't work! However, I wrote some test-images of less than 1K and the ...

I found a UK seller. My only worry is programming the thing.

Thank you! Will purchase another one next week.

The problem is that the pinout is different from the ones needed for the UK101. The one I have is 64K.

Atmel 28C64B

I just realised, the Atmel EEPROM I've been trying to program is incompatible with the UK101 because of the difference in pinouts. So I will have to purchase an old 28 pin EPROM/EEPROM. BigEd, once I get paid I will need you kind help! Thanks in advance!

I read somewhere that ROMs have to erased before writing. I wonder if that stops me from being able to write my EEPROM? I checked the datasheet and the erasing waveform looks identical to the writing one except the erasing pulse takes longer (10ms as opposed to the 100ns of writing) and the output ...

Indeed it's a 28 pin DIP however it only needs 5 volts for programming. Dajgoro is helping me debugging the EEPROM programmer contraption but if it fails I'll need your help. Thank you!

Gentlemen, is there anyone who could burn EEPROM for me in the UK? I've been struggling with a home made contraption and doesn't seem work properly.

Also, I recommend using WW headers to distribute the power: http://spiratronics.com/product-39395.html One post is not enough to wire all the ICs to so I used four pairs (VCC+GND) of headers placed at different points of the board, all connected to one pair. Do not daisy chain!

Somone noted in a blog that WW is like meditation. I totally agree. You don't need the soldering iron, only a spool of kynar and the tool and it can be done while watching a movie. I already miss WW-ing. Gotta find an other SBC to build...