| Attachment | Size |
|---|---|
 Apple II+ Clone (Unicom) | 2.27 MB |
I've recently restored this Apple II+ Clone. It has a UM2316 as character ROM. The Chip itself is replaceable with a 2716 eprom. But none of the standard Apple II Character ROMs works.
The connection between the ROM and the 74166 totally diffrent from what it is in a regular II+.
Does anyone regognize this board? Are there any Informations / ROM images available anywhere?
It's a generic clone and will use CG image all the clones use. If you don't have an image from a clone let me know and I can dump one from one of the clone boards I have here.
A 2316 is not programmable, it is a mask ROM.
The programmable version, 2716, requires +25V programming voltage, which is not supplied by most of the low-cost programmers now available. Refer your programmer's documentation for whether it can supply such a voltage (or better yet, look up any devices in its published device list).
There are versions of the 2716 that require +21V or less. 27C16 and some marked 2716 will work, it just depends. TI also had a 2516 back in the day that only required +12V for programming if I remember right.
Also some people have had luck supplying their own 25V programming voltage and gotten newer programmers to work. FWIW, I have an older MiniPro TL866CS which I've successfully programmed a lot of 2716s with. Others claim it doesn't work for them. Most report the newer TL866-II does not work.
Dear robespierre, dear softwarejanitor,
have many thanks for your answers.
yes, I know, that the 2316 is a ROM (I thought it would be a PROM, that could be programmed once...).
But ideed, I planned to exchange the 2316 by an EPROM, like 2716 or better by an EEPROM, like a 27/28C16.
And yes, my search in the net brought me also to the TL866 programmer...
Okay, I'll search a while for a TL866A or'll use a TL866 II to use it for the newer 27/28C16. Does this function good?
Sorry for my pure english...
Best Regards
Georg
That is a fairly common Unitron - style (or true Unitron) motherboard.
There is no real difference in Character Generators between them.
If you need one, I can supply an image, or a burned 2716 EPROM in exchange for you sending me a blank.
Most USB programmers will fail at programming 2716s. I have a vintage burner that works on 2716s. 100% success rate.
I'd be happy to help.
The TL866CS is the old version which is difficult to find, if you don't have that one already.
What is sold today is the TL866II+ which can't program some of these old eproms.