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by on (#118351)
:shock: I stumbled across your forum while looking for information re my sewing machine!!! Juki ams 206 A. One of the first computer controlled machines(industrial). Probably somewhere around 1982-6. I have found a program that will format for it but I need an e or eeprom writer... There are so many and such a giant price range, I am hoping I can get some advice. Apparently the program, Embird, sends my design to a floppy disk drive and then it needs to be written on the eprom . The # on the prom in the sewing machine is M5L2764K (it may be erasable there is a sticker over the back) I have no idea what i need for a writer or where to get the chips. I"m assuming that I need one? I have learned more during this search than I ever thought I could. I'm surprised my little pea brain hasn't exploded yet, since you can't see I'm knocking on wood, with my head. Any advice would be gratefully appreciated
Re: help???
by on (#118361)
The part is an 8KB EEPROM. Datasheet here.

Quick search for a prorgrammer - googled "M5L2764K programmer" - yielded this.

But I'm sure there are other cheaper and more...uh...up-to-date...models. Parallel port?!?
Re: help???
by on (#118410)
Heh, the datasheet calls it "erasable and electrically programmable ROM", which mislead me too. It actually is a windowed EPROM rather than EEPROM.

To erase it you'll need a UV EPROM eraser. Also since it seems to have a standard pinout, you should be able to use any 2764 or 27C64 part (27C64 will probably be supported by more of the cheaper programmers). It may be possible to use 27C256, depending on what the device does with pin 26 (it can't be left unconnected, though), which may be easier to find. You would just duplicate the data multiple times (it's 4 times larger).

If you don't need to change the ROM data very often, there are people that can burn ROMs for you, for a small fee.

On an unrelated note, years ago I remember finding some references to there being a Famicom-controlled sewing machine.
Re: help???
by on (#118411) will sell you programmed memories. One stop shop for a situation like this, no need to buy the programmer for a one time use.
Re: help???
by on (#118578)
So I"ve spent the last couple days googling to make sure i understand what u guys told me... I think i do...(I hope) the paralell port thing I still don't get, but from the other 2 does one say that i can use any (chip,card) ? as long as it has 2764 in the name ? Or the right # of pins ? My local computer guy said he needs part # and the connection type. ie usb or one of the plug in things...and the words "plug in things" should probably tell u a lot. Please don't give up on me I"m trying to learn as much as I can as fast as i can.
Re: help???
by on (#118581)
by plug in things i mean what connects to computer to the writer. Sorry it must be such a bitch to try and help someone like me. I wish I knew how to put an embarassed smiley face here.
:oops: never mind just found the icon :!: :!: :!:
Re: help???
by on (#118582)
1) nearly identical part match, although any 8KB EPROM will probably do:

2) USB programmer: ... c=1&_gtc=1 Follow instruction manual.

2 ALT)Don't want to spent $50 on a one time use programmer? Just contact buyicnow and provide them the chip and they can program it for you.

3) put in your device for end use.
Re: help???
by on (#120719)
Hi its me again.... I have the writer and M5L2764K eproms. Sadly the writer supports the same one only without the K on the end. I have found what google tells me is an equivalent, an intel 2764 and the writer does support it so I tried to choose the intel one in the menu but it still says theres an error and nothing on the eprom. (still using the m5l2764k) Am I just not even smart enough to run the point and click on the writer, or do I have to have the exact same letters and numbers on the eprom ? I hope theres not another problem that I just cant even see yet. grrrrr I can't find any 8kb that will work with the writer.
Re: help???
by on (#120771)
The chip you have needs a 21-volt power supply during the programming process. This is common with very old UV EPROMs. My guess is the GAL G540 does not support this, as it is a USB-powered programmer (USB only provides 50 mA at 5V). Sorry about the confusion :(

this is a pin-compatible chip that is in current production. It retails for about $4 USD in single quantities and is available for immediate purchase at the link above. It's also available at most other distributors like DigiKey. See if your GAL programmer manual says it supports this guy. My guess is it does.

Another nice thing about this chip is that it's an EEPROM, which means Electronically Erasable PROM. If you ever need to change the patterns in your machine, you can pop this chip back out, erase it with your programmer and program it again with something new. There's no need for a UV lamp to erase it. Each chip is good for at least 100,000 erase / program cycles. And trust me, you'll snap the pins off of this thing long before you hit 100 :)

Finally, don't be shy about asking about old tech around here. We're a very warm and welcoming community, and we love to tinker with old tech.

Best of luck!