Could anyone help us find an old very early 8086 uP for our University's SEM? It is a very old unit be our Scanning Electron uScope will not operate untill we find one. I think the speed is either 1 or 4MHz. It is imprtant we get one of the earliest version.
I have some NMOS 80188 chips, in ceramic PGA and an odd flat ceramic package. I have an 80C188 in PLCC too. I can't recall if the 8088 came in anything other than DIP40.
Phillips used 8086 in their ~ 1978-85 TEM, I forget what the model number is ! I don't recall what they used in their 1980s SEM. I have forgotten what was so special about the 8086/ Z80/ 8080/ 8085/ 8088. Gee that was 25 years ago.
IIRC, the 8086/8088 were among the first microprocessors to utilize segmentation to reach a 1MB address space using what was actually a
16-bit CPU. Shift a 16-bit segment register left 4 bits, add 16-bit offset, 1MB addressibility results. Every programmer in any language on this CPU approached memory management with care. They knew that there was actually a maximum of 640KBs available, because the remaining
360K on PC-compatibles was reserved for things like video frame buffers and boot ROM. I think the difference between 8086 and 8088 was that
8086 had a true external 16-bit data bus, whereas 8088 had only 8 bit bus with double-cycling. The initial, "standard" speed of 8088/6 was
4.77 MHz.
A lot has changed since then. Today, if you fire up Limewire on Windows, you can see it (and the Java diaper that comes with it) unapologetically consuming 60 megabytes of of RAM. The ubiquitous Adobe Acrobat eats up 52 MB.
That should not be too hard, try for example Strixner & Holzinger
formatting link
They claim to have five different Intel versions of the 8086 on stock in small quantities plus several second source 8086's. So far I always got what their site showed within 14 days or faster at reasonable prices - not cheap, but reasonable.
The 8086 was the 16 bit data buss version of the 8088 used in the IBM PC & XT computers. IBM used the 8088 because it only had an 8 bit data buss.
The 8086 turns up on E-bay, and some electronic surplus places list them from time to time. I might have one, but I would have to dig through about 100 boxes of early computer boards to find one.
--
Service to my country? Been there, Done that, and I've got my DD214 to
prove it.
Member of DAV #85.
Michael A. Terrell
Central Florida
If you could send one to the university, give me you email (or send me an email but remove the word -nospam from this snipped-for-privacy@wlawson-nospam.co.uk) and I will contact you with the postal address? We can give you a token amount which includes the postage, please let me know in the email. I can pay by paypal. Are you in the UK?
I knew if i kept that original '84 IBM PC it might be useful to someone or worth something again one day now if i could get the original price for i would be very happy ;)
good luck fnding one if you exhaust your other sources then post back here if my cpu will help you
I saw a lot of the same 8 bit cards used in some of their dedicated word processing systems. The same video board, floppy controller, printer port, monitor and even the original five slot "PC" case. The "XT" was the same design, except they moved the slots closer together to add the three additional slots. Do you remember the little metal plate with a single screw covering a rectangular hole on the back of the PC case? It was used in the word processing system. BTW, the word processor used the 8085 & support chipset.
--
Service to my country? Been there, Done that, and I've got my DD214 to
prove it.
Member of DAV #85.
Michael A. Terrell
Central Florida
ElectronDepot website is not affiliated with any of the manufacturers or service providers discussed here.
All logos and trade names are the property of their respective owners.