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Re: Fake Kynar wire-wrap wire
Posted: Sun Jul 04, 2021 6:33 am
by BigDumbDinosaur
Now I'm really confused. When I went to the ISSI website they had no info on any skinny DIPs made for the product #'s my IC's have. So they are functional fakes?
I guess I'll have to wire it up and see what happens.
I've been using ISSI RAMs in my POC units since their inception. I have never seen an ISSI part that wasn't in some type of SMT package...SOJ32 in the case of the 128KB RAM I have used.
Re: Fake Kynar wire-wrap wire
Posted: Sun Jul 04, 2021 6:51 am
by BigDumbDinosaur
No sir. I quote:
- The IS61C1024AL/IS64C1024AL is available in 32-pin 300-mil SOJ, 32-pin 400-mil SOJ, 32-pin TSOP (Type I, 8x20), and 32-pin sTSOP (Type I, 8 x 13.4) packages.
None of my ISSI data sheets has ever indicated their SRAMs are available in a skinny DIP. The "skinny" package is likely an SOJ32 × 300 mil, same as I use in my POC V1 units. See attached—SRAM is highlighted in a bluish (I think—I'm blue-green colorblind) rectangle.
- SOJ32 × 300 mil ISSI SRAM
Re: Fake Kynar wire-wrap wire
Posted: Sun Jul 04, 2021 9:44 am
by 1024MAK
ISSI definitely did produce 32K byte SRAM in 28 pin skinny DIP/DIL form. I have an old PC motherboard with bunch of them on. See photo…
- ISSI IS61C64AH-20N SRAM with a date code of 9327
ISSI may be like some other semiconductor companies, in that they only keep datasheets of their current range online. So if they have stopped manufacturing DIP/DIL (very likely) for some of their products, they will either have removed the datasheet from being online (assuming it was ever online in the first place) or will have revised it to remove all details of discontinued packages.
Mark
Re: Fake Kynar wire-wrap wire
Posted: Sun Jul 04, 2021 2:41 pm
by enso
BDD, you are no doubt correct about current ISSI chips. I was saying that in the past, I've seen ISSI caches with narrow DIP packages. The photo confirms my somewhat unreliable memory...
Re: Fake Kynar wire-wrap wire
Posted: Sun Jul 04, 2021 4:31 pm
by BigDumbDinosaur
BDD, you are no doubt correct about current ISSI chips. I was saying that in the past, I've seen ISSI caches with narrow DIP packages. The photo confirms my somewhat unreliable memory...
Yes, I am referring to "current" (the last 15 years) production. DIP caches had their day in the early-to-mid-1990s.
Re: Fake Kynar wire and not fake ISSI SRAMs
Posted: Sun Jul 04, 2021 6:05 pm
by enso
In that case, BDD, I am not sure what your objection is.
Re: Fake Kynar wire and not fake ISSI SRAMs
Posted: Sun Jul 04, 2021 8:41 pm
by ThisWayUp
So basically I just need to test the chips. I better get up to speed on how to do that. Being a newbie with all this stuff sucks
But I am definitely getting a crash course in how the real hardware works. I feel like I've learned more about how computers and electronics in general work in the last month than I ever did messing around with Arduino or tinkering in Python or C++. And I thought I was making real headway when I wrapped my mind around the basics of DC circuits and standard passive components.
Re: Fake Kynar wire and not fake ISSI SRAMs
Posted: Mon Jul 05, 2021 12:16 am
by enso
ThisWayUp, a word of advice: unless you enjoy really frustrating experiences, the first time around just order your parts from Mouser or some other reputable source. I love bottomfishing on EBay and AliExpress, but it is a lot easier to put together a W65C02 computer with known-good parts. You can then swap in questionable parts, one at a time, and see if it still works. The other way around, you will be sitting there with a dead machine, wondering where to start.
Re: Fake Kynar wire and not fake ISSI SRAMs
Posted: Mon Jul 05, 2021 1:36 am
by BigDumbDinosaur
ThisWayUp, a word of advice: unless you enjoy really frustrating experiences, the first time around just order your parts from Mouser or some other reputable source...The other way around, you will be sitting there with a dead machine, wondering where to start.
Adding insult to injury, your bargain eBay parts could cause damage to your good parts when you put power to your machine if the stars and the moon are aligned the wrong way.
Although the logic behind it completely baffles me, 65xx parts are widely counterfeited. We have had topics on that around here, so it may be worthwhile to find them and learn more about this stuff. When it comes to purchasing 65xx parts, your safest bet will always major electronics distributors who have a reputation to protect.
Incidentally, there are no authorized distributors of WDC parts in China. If a Chinese seller is offering 65C816s, etc., it is very likely they are selling fakes.
Re: Fake Kynar wire and not fake ISSI SRAMs
Posted: Mon Jul 05, 2021 4:40 am
by GARTHWILSON
Although the logic behind it completely baffles me, 65xx parts are widely counterfeited. We have had topics on that around here, so it may be worthwhile to find them and learn more about this stuff.
Re: Fake Kynar wire and not fake ISSI SRAMs
Posted: Mon Jul 05, 2021 2:11 pm
by TomC
The 1996 and 1998 versions of the IS61C1024 datasheet include the 300 mil DIP package (1996 lists a 400-mil DIP as well). It was removed in the 1999 version.
I'm trying to determine if the MC6828s I bought are real & functioning but I'll make a separate thread for that.
Re: Fake Kynar wire and not fake ISSI SRAMs
Posted: Mon Jul 05, 2021 5:44 pm
by ThisWayUp
ThisWayUp, a word of advice: unless you enjoy really frustrating experiences, the first time around just order your parts from Mouser or some other reputable source. I love bottomfishing on EBay and AliExpress, but it is a lot easier to put together a W65C02 computer with known-good parts. You can then swap in questionable parts, one at a time, and see if it still works. The other way around, you will be sitting there with a dead machine, wondering where to start.
Yes, I have definitely learned my lesson on that now. I do have all legit chips for my current built. I'm using a Renesas 7164 64k for my RAM.
Adding insult to injury, your bargain eBay parts could cause damage to your good parts when you put power to your machine if the stars and the moon are aligned the wrong way.
Although the logic behind it completely baffles me, 65xx parts are widely counterfeited. We have had topics on that around here, so it may be worthwhile to find them and learn more about this stuff. When it comes to purchasing 65xx parts, your safest bet will always major electronics distributors who have a reputation to protect.
Incidentally, there are no authorized distributors of WDC parts in China. If a Chinese seller is offering 65C816s, etc., it is very likely they are selling fakes.
Good to know about the chinese distributors, or lack there of. I was initially losing my mind after I found out the 65c02 I had originally gotten from Amazon was a fake, I was concerned it had nuked my other chips, but I got lucky. I do have to admit this has been an extremely harrowing experience, something I was not expecting
Re: Fake Kynar wire and not fake ISSI SRAMs
Posted: Wed Jul 07, 2021 1:23 am
by enso
...I've learned more about how computers and electronics in general work in the last month than I ever did messing around with Arduino ...
Re: Fake Kynar wire and not fake ISSI SRAMs
Posted: Wed Jul 07, 2021 1:44 am
by ThisWayUp
I actually lost interest when my progress was halted by everyone trying to pimp their own libraries , trying to use an IDE that made me want to skip my computer off the pavement, and finding out that 99% of the hardware sold to Arduinoheads its literally just $0.25 IC's on breakout boards for $15.00.
You can do a lot with Arduinos, but in order to do alot you have to basically write everything from scratch and know how all the hardware works anyway, so theres not much point, my 2c.
Re: Fake Kynar wire and not fake ISSI SRAMs
Posted: Wed Jul 07, 2021 2:31 am
by BigDumbDinosaur
I feel like I've learned more about how computers and electronics in general work in the last month than I ever did messing around with Arduino or tinkering in Python or C++.
This is something Garth and I have been preaching for some time.
The Arduinos and Raspberry PIs of the world have their place. If your goal is to quickly throw together a circuit to implement a specific function, "canned" electronics of this type have a lot to offer. On the other hand, if you want to learn how it all works and gain the satisfaction that comes from designing and building a working computer from basic logic gates, a microprocessor, and some memory, Arduinos and Raspberry PIs aren't going to have much to offer.