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Re: My first try at EPROMs
Posted: Sat Nov 11, 2017 6:38 pm
by eslapion
Floopy wrote:What would you use 2K eproms for?
If I skip the fact you were dividing by 16, 2K EPROMs are 2716 and the tape accelerator 'The Rabbit' used that.
Re: My first try at EPROMs
Posted: Sat Nov 11, 2017 7:34 pm
by norm8332
I mainly use the 4K ones for Atari 2600 homebrews or prototypes etc.
Re: My first try at EPROMs
Posted: Sat Nov 11, 2017 7:36 pm
by norm8332
Floopy wrote: I was dividing by 16
I'm only making myself look even more ridiculous.
Not so, that's what forums are for, we all have to learn somewhere.
Re: My first try at EPROMs
Posted: Sat Nov 11, 2017 8:23 pm
by Floopy
norm8332 wrote: we all have to learn somewhere.
True...
I like the way those cartridges look, I thought they where real ones at first. I'm glad that it's cheaper to make your own seeing how prices are starting to rise.
Re: My first try at EPROMs
Posted: Sat Nov 11, 2017 9:39 pm
by norm8332
I mainly make them because I can
I'm one who always needs a project.. If I can build it, I will.. and use the (sometimes tiny) savings to justify it. BTW off topic I posted that case design awhile back if anyone needs one
https://www.thingiverse.com/thing:1790785
Re: My first try at EPROMs
Posted: Sat Nov 11, 2017 11:02 pm
by Floopy
norm8332 wrote:I'm one who always needs a project.. If I can build it
Same here, my only issue is time
. I go to school and I spend 20% in class 70% homework 5% dreaming over projects and 5% doing the projects.
I always try to build what I can, I built the furniture for all my computers and basement.
Cartridges design is the thing I can do well, I use CAD software all the time.
Re: My first try at EPROMs
Posted: Sun Nov 12, 2017 4:08 am
by eslapion
norm8332 wrote:...
Not so, that's what forums are for, we all have to learn somewhere.
That's the spirit!
Re: My first try at EPROMs
Posted: Thu Nov 16, 2017 11:28 pm
by norm8332
eslapion wrote:norm8332 wrote:Ebay is literally flooded with these "new" ST EPROMS right now.
Yeah, the datecode (1035) is quite interesting. There is no way SGS-Thomson was making more 2732 EPROMs in late 2010.
Also look at the size of the die. I have real 2732s here and they are 4 times bigger.
FYI: After closer inspection of these EPROMs Die(s) with my cheap new video microscope, I believe they are refurbished (cleaned) and remarked. They have the die markings of Mostek, SGS-Thompson and ST. It's just the Chinese recycling "junk" again. They work fine though.
Re: My first try at EPROMs
Posted: Fri Nov 17, 2017 9:52 am
by Floopy
I'll have to try that today!
I am have a microscope that can zoom
in through the window. I've done this before with Intel Eproms, I love to see the silicon.
Re: My first try at EPROMs
Posted: Fri Nov 17, 2017 10:32 pm
by Floopy
So deviating from the subject (even though it still fits under this post).
I've acquired a lot of chips. On inspection of components I found several Eproms and a few chips I can't find what there purpose is. Can someone help me with them some of them I don't know there functions at all.
#1: this one reminds me of the 6522 but I don't think they are alike in anyway.
#2: I have not an idea what this one does.
#3: I know this is an Eprom but I can't find much info on it. My programmer does not list it anywhere
The number is faded out here it is: HN462716G
And last of all I received some D2732 and D2716 but they are all 24 pins??? Please bear with my ignorance as I'm just beginning.
Re: My first try at EPROMs
Posted: Fri Nov 17, 2017 10:36 pm
by Floopy
Some are chipped but they look beautiful (at least I think so). A lot of them where labeled with BASIC 1,8 or 4 and they had a version of basic with a copyright code of 1977.
the picture is bad but they are a light brown and the one pictured was one of the worst ones. They all work though!
Re: My first try at EPROMs
Posted: Fri Nov 17, 2017 11:42 pm
by eslapion
Floopy wrote:And last of all I received some D2732 and D2716 but they are all 24 pins???
Yes... EPROMs have 28 pins starting at 2764 which is 8kx8.
Usually, people have a surprise the other way around. ROMs 2364 carrying 8kx8 bits used in the VIC-20, C64 and 1541 drives have only 24 pins yet their EPROM counterpart has 28 pins and an adapter is required.
Re: My first try at EPROMs
Posted: Sat Nov 18, 2017 1:46 am
by srowe
Floopy wrote:
#1: this one reminds me of the 6522 but I don't think they are alike in anyway.
This is a 6551 ACIA, the RS-232 chip that was intended to be used in the VIC but wasn't available in time.
Re: My first try at EPROMs
Posted: Sat Nov 18, 2017 7:25 am
by MCes
R6551 is ACIA (serial interface) used into Commodore PLUS4,
PAL16L8 is a PLD (Programmable Logic Devices), it seems programmed and can't be erased...
HN462716G is a 2k byte EPROM like as a normal 2716,
2732 is a 4k bytes eprom,
2764 is a 8k bytes eprom....
Re: My first try at EPROMs
Posted: Sat Nov 18, 2017 11:24 am
by Floopy
MCes wrote:
HN462716G is a 2k byte EPROM like as a normal 2716,
2732 is a 4k bytes eprom,
.
My programmer does not seem to support it, it's okay though I have others. Another question can you use 4Kb eproms to replace 8Kb, I mean if I find a version of basic that fits on a 2732, can I directly insert it into the socket no adapter. I found this site and it looks like they can be used as a direct replacement?
https://ist.uwaterloo.ca/~schepers/roms.html
eslapion wrote:
Usually, people have a surprise the other way around. ROMs 2364 carrying 8kx8 bits used in the VIC-20, C64 and 1541 drives have only 24 pins yet their EPROM counterpart has 28 pins and an adapter is required.
Well in my case I found out about these 35 years after they were made.
srowe wrote:
This is a 6551 ACIA, the RS-232 chip that was intended to be used in the VIC but wasn't available in time.
This was what I was guessing, it's an interface device.