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Re: Smonson's slow H4 build
Posted: 14 Jan 2020 07:54
by kodak80
@Smonson I have purchase from this seller a few times and components have worked fine.
They also sell them in 5 packs:
https://www.ebay.com.au/itm/5pcs-HN27C4 ... 2103004850
Re: Smonson's slow H4 build
Posted: 14 Jan 2020 09:48
by exxos
Smonson wrote: 14 Jan 2020 06:47
I never cease to be amazed that you can buy 32GB of flash for $10 and yet a chip with less than a meg on it can be the same price or more.
Try buying 100 of them each time like I have to :lol: :roll:
Re: Smonson's slow H4 build
Posted: 14 Jan 2020 10:09
by Smonson
exxos wrote: 14 Jan 2020 09:48
Try buying 100 of them each time like I have to :lol: :roll:
Ummm, I might pass... :lol:
Re: Smonson's slow H4 build
Posted: 14 Jan 2020 15:10
by PaulJ
Smonson wrote: 14 Jan 2020 04:17
Thanks @PaulJ. Gosh they're not cheap for a OTP, are they :shock:
Ya you're right but I have good reason for buying quality OTP. Initially with the Remake board I purchased 4 of the EEPROM Kodak80 listed. I did this because I was putting together the images for the OTP chips and I didn't want to be able erase and reprogram. The first failed in about 10 minutes.. stone cold dead, the remained 3 appeared to be running fine. When I built my 1.04/DiagROM I could not get the DiagROM half to run no matter what I did. Tried a second EEPROM.. same shit. Put them in the eprom programmer and would tell me I had the programmed image. Finally out of despiration I tried the third and last EEPROM. It worked!!!! SAME IMAGE! I had wasted days playing with eBay cut rate crap. So from that point on I made sure to get quality prom devices. I still use the EEPROMS but if they don't work I don't take that as a bad image. At that time @Phil was having the same issue. So if it fails to work don't assume you have a bad image.
So I wasted about 20 hours of effort and a lot of head scratching.. its worth a few bucks to me to avoid massive loss of time and dealing with a issue that makes no sense.
Re: Smonson's slow H4 build
Posted: 15 Jan 2020 02:44
by kodak80
I had issues programming the OTP chips and I binned 6 chips through programming fails. I switched to the UV erasable ones and also had programming issues which turned out to be a worn ZIF socket on my programmer.
I have found on my new programmer that the UV chips need to be held in the adapter to ensure all pins are connected and programming works 9 times out of 10 but even if it fails I can erase them and try again. I have not yet had one that I could not program.
Re: Smonson's slow H4 build
Posted: 15 Jan 2020 03:18
by PaulJ
kodak80 wrote: 15 Jan 2020 02:44
I had issues programming the OTP chips and I binned 6 chips through programming fails. I switched to the UV erasable ones and also had programming issues which turned out to be a worn ZIF socket on my programmer.
I have found on my new programmer that the UV chips need to be held in the adapter to ensure all pins are connected and programming works 9 times out of 10 but even if it fails I can erase them and try again. I have not yet had one that I could not program.
Ya, when making a new image I use the erasable and after it works burn a OTP. I've trashed a few of the OTP's when I think I couldn't screw it up.. but do.
Re: Smonson's slow H4 build
Posted: 25 Feb 2020 07:53
by Smonson
Got most of the passives on now, and I've got a SIMM socket coming. I started depopulating my donor board. The first thing I ran into was the reversed reset switch footprint. I don't really want to bend the switch to make it fit - I might just drill a couple of extra holes for the shield. Has anyone else done this successfully?
Re: Smonson's slow H4 build
Posted: 25 Feb 2020 08:34
by exxos
Don't drill holes, you risk shorting out the internal power planes.
Re: Smonson's slow H4 build
Posted: 25 Feb 2020 08:39
by Smonson
Hmm, okay, I won't be doing that then!
Re: Smonson's slow H4 build
Posted: 25 Feb 2020 09:01
by exxos