The Sinclair QL Forum

Pr0f wrote:In that DIY Arduino programmer - the inventor there suggested there may be some timing issues for certain signals that can affect the programming - reading was ok, but program / verify could fail - I did wonder if the HiLO units were meeting all the timing specs - they certain do meet the voltages outlined in the 8749 programmers guide - it seemed to vary by chip manufacturer too.

Never had a single chip fail me in the Arduino programmer, yes.

Hi,

The 8749 chips that I stated were faulty,I was issued a refund and allowed to keep the chips, so maybe my ALL03a programmer is not up to the job.

Here is another link of someone who has built an the Arduino MCS-48 Shield:
http://www.bygonebytes.co.uk/8748_Programmer.html

I will have to get an Arduino Mega and get short shield PCBs made.

anon wrote:I purchased about 50 MCS-48 samples when designing my programmer, and blew a quarter of them discovering this.

Sounds like number 13 was when the penny dropped...

Derek_Stewart wrote:I note there is a DIY Progammer:

http://www.mattmillman.com/projects/hve ... er-reader/

Which,looks easy to build, I will get some PCBs made.

A few PCBs available here : https://www.ebay.co.uk/itm/125415325819

ones' complement wrote:

Derek_Stewart wrote:I note there is a DIY Progammer:

http://www.mattmillman.com/projects/hve ... er-reader/

Which,looks easy to build, I will get some PCBs made.

A few PCBs available here : https://www.ebay.co.uk/itm/125415325819

I had some Blue PCBs made to match the test of the system... just waiting to be made.

There were some 8749's that were plastic OTP versions - I got some on ebay that were supposed to be blank, but had one byte programmed in the middle of memory, and sadly not a byte that was unused on the IPC program. They all had the same issue.

At least with the glass ones, you can UV erase. The label will most likely be covering the window from the picture I can see.

Hi,

As I mentioned earler, I bought 10 Intel D8749H IPCs, only 2 out of 10 were abled to be programmed with the ALL03A programmer with the Hetmes code, after erasing them in a UV Eraser.

Here is one of the D8749H IPC in a Issue 7 QL: I usually put a better label over the UV Window....

I got a refund on the 8 chips, and they did not want them back, so I could see if there is a probl yhr chips or thr ALL03A programmer.

I will have build a HVEprom programmer as well.