z80b microprocessor has rom? - Page 1
Forum section: electronics / projects

author: SArepairman
author_rank: Frequent Contributor
timestamp: July 19, 2013, 07:57:47 am
content: So, I might need to replace a Z80B. Is this thing just a CPU or is it like a modern micro controller where it has some build in read only memory?as far as I understand from bits of information online it does not have any ROM.

author: deephaven
author_rank: Frequent Contributor
timestamp: July 19, 2013, 08:00:23 am
content: It's just amicrocontrollermicroprocessor, no built in RAM or ROM.Edit: Corrected slip of the brain!

author: fcb
author_rank: Super Contributor
timestamp: July 19, 2013, 08:02:10 am
content: Not a microcontroller! It's a microprocessor - and no, it has no onboard ROM or RAM or conventional IO.

author: amyk
author_rank: Super Contributor
timestamp: July 19, 2013, 10:32:14 am
content: Technically it does have an internal instruction decode ROM but that's probably not what you were looking for.

author: PA0PBZ
author_rank: Super Contributor
timestamp: July 19, 2013, 10:56:55 am
content: If I remember correctly the B stands for the super fast 6MHz version

author: grumpydoc
author_rank: Super Contributor
timestamp: July 31, 2013, 09:52:44 am
content: QuoteBy the early/mid 80's they were up to 8MHz. My SGS Z80 data book lists:"Plain" Z80 2.5MhzZ80A 4MHzZ80B 6MHzZ80H 8MHzYou can get 20Mhz parts these days.

author: amyk
author_rank: Super Contributor
timestamp: July 31, 2013, 10:54:28 am
content: Quote from: grumpydoc on July 31, 2013, 09:52:44 amOr 100MHz+ on an FPGA.Some MP3 playershad a 24-60MHz Z80 core ASIC.

author: IanJ
author_rank: Unknown
timestamp: July 31, 2013, 11:07:14 am
content: There was the Z280 also. It ran the Z80 instruction set plus more........16-bit in a PLCC68 package.Out of interest.........Late 80's we used the Z280 extensively on one of companies core products, then Zilog withdrew it........as it had a fundematal problem. Aaaaarrgghhh, I remember going all out to buy all I could........we spent a few thousand pounds buying over 200 of them.I left the company years ago, but they are still bulding the boards.....no SMD in sight. It was routed using Wintek's HiWireII. Ahhhh, them thar days!Ian.

author: minibutmany
author_rank: Regular Contributor
timestamp: August 01, 2013, 04:41:50 pm
content: I have always had an interest in Z80 systems. What are you working on?

author: asgard
author_rank: Regular Contributor
timestamp: August 01, 2013, 04:46:52 pm
content: Oh goody, Zilog parts. Does anybody else remember the Z8000's? I used to be the admin at UCSC's only connection to the Berkeley campus, which was a desktop Onyx computer with Z8000 running version 7 UNIX and an 8" Winchester drive.

author: jeroen74
author_rank: Frequent Contributor
timestamp: August 01, 2013, 04:56:59 pm
content: Back in the nineties I designed a product with a Z182, which is a Z180 with some nice extra goodies, the important one the (IIRC) ASSC; which was the only synchronous serial controller capable of properly talking HDLC to some weird industrial machine (which probably used the Zilog ASCC too).The Z182 also had a 'MIMIC" which allowed direct connection to a PC ISA bus where it looked like a 16550 compatible UART. Made for a simple interface.Basically an EPROM, SRAM, GAL, Z182 and a couple of RS485 transceivers. In a later revision the EPROM, SRAM and GAL were replaced by a PSD854.

author: dfmischler
author_rank: Frequent Contributor
timestamp: August 02, 2013, 01:22:47 am
content: Quote from: asgard on August 01, 2013, 04:46:52 pmI never actually used or programmed one, but I remember whoever was rep'ing the Zilog stuff in my area coming through and trying to build mindshare in the engineers. Left plenty of data books and would have left samples if we asked. Most (all?) of the microprocessors we designed in to our systems at that time were Motorola 680x and 68000 family parts.

author: asgard
author_rank: Regular Contributor
timestamp: August 02, 2013, 02:38:59 am
content: I remember that I had been "cooking up" code for my Heathkit with the 8080A for about a year, when Z80's really started up (blame goes to George Morrow, rather than Bill MillardI eventually got a job under Morrow writing UNIX manuals for a Z80 system (GACK). I just had my little octal cheat sheet that nobody was using, but it helped me decompose the binary on sight. When Zilog put the feeny weenie opcodes for the IX and IY registers it blew up my numeric system so bad I never used it. Good old BCDEHLMA sequence was pretty good up to then.

author: free_electron
author_rank: Super Contributor
timestamp: August 02, 2013, 03:03:36 am
content: Quote from: IanJ on July 31, 2013, 11:07:14 amoh my... i still shiver when i think about smartwork. F1 place pad , f2 remove pad , f3 place trrack ,f4 remoce track , f5 toggle width of trackdip 40 600 e .. give ma 40 pin dip 600 il pitch eastern orientationi did at least over 100 boards in that thing... 1986 to 1990. Then i discovered Protel Autotrax under dos which through the years evolved into Altium Designer.. never looked back since.

author: IanJ
author_rank: Unknown
timestamp: August 02, 2013, 07:59:05 am
content: Quote from: free_electron on August 02, 2013, 03:03:36 amWow, you still remember the keyboard commands!........I can't remember what it looked like on-screen....nothing!........although I do remember it ran off 5.25" floppies, one of them being the key un-copyable floppy that had to be in the PC at all times.When we upgraded to HiWireII I thought all my Xmas's had come at once!Ian.