Send cctalk mailing list submissions to cctalk at classiccmp.org To subscribe or unsubscribe via the World Wide Web, visit http://www.classiccmp.org/mailman/listinfo/cctalk or, via email, send a message with subject or body 'help' to cctalk-request at classiccmp.org You can reach the person managing the list at cctalk-owner at classiccmp.org When replying, please edit your Subject line so it is more specific than "Re: Contents of cctalk digest..." Today's Topics: 1. Re: Happy Birthday VAX 11/780 (influence of) (Chuck Guzis) 2. Re: TTL HEX LED driver chip (Chuck Guzis) 3. Re: TRS-80 Model II Manuals (Fred Jan Kraan) 4. Re: DiscFerret: First working hardware, firmware and microcode! (Philip Pemberton) 5. Re: TRS-80 Model II Manuals (Tony Duell) 6. Re: TRS-80 Model II Manuals (Chuck Guzis) 7. Re: DiscFerret: First working hardware, firmware and microcode! (Dave McGuire) 8. Re: Happy Birthday VAX 11/780 (influence of) (Dave McGuire) 9. Re: DiscFerret: First working hardware, firmware and microcode! (Philip Pemberton) 10. Re: TTL HEX LED driver chip (Brent Hilpert) 11. Re: Happy Birthday VAX 11/780 (influence of) (Brent Hilpert) 12. Fall cleaning, some small machines for free (Bob Rosenbloom) 13. Re: DiscFerret: First working hardware, firmware and microcode! (Chuck Guzis) 14. Need to find parts 82S23 / 74S188 (alan canning) 15. Re: Happy Birthday VAX 11/780 (influence of) (Chuck Guzis) 16. Re: DiscFerret: First working hardware, firmware and microcode! (Philip Pemberton) 17. Re: TTL HEX LED driver chip (Tony Duell) 18. Re: Nuclear Data ND 6600 (Tony Duell) 19. Re: TRS-80 Model II Manuals (Tony Duell) 20. Re: TTL HEX LED driver chip (Tony Duell) 21. Re: TTL HEX LED driver chip (Tony Duell) 22. Re: Wanted : Monitor Capable of TTL RGB (Tony Duell) 23. Re: I/O models (was RE: Happy Birthday VAX 11/780 (influence of)) (Tony Duell) 24. Re: Fall cleaning, some small machines for free (Brent Hilpert) 25. Re: Need to find parts 82S23 / 74S188 (ben) 26. Re: TRS-80 Model II Manuals (Geoffrey Reed) 27. Re: Need to find parts 82S23 / 74S188 (Tony Duell) 28. Re: Need to find parts 82S23 / 74S188 (Chuck Guzis) ---------------------------------------------------------------------- Message: 1 Date: Sat, 30 Oct 2010 10:08:19 -0700 From: "Chuck Guzis" <cclist at sydex.com> Subject: Re: Happy Birthday VAX 11/780 (influence of) To: "General Discussion: On-Topic and Off-Topic Posts" <cctalk at classiccmp.org> Message-ID: <4CCBEE93.7369.1A49AC at cclist.sydex.com> Content-Type: text/plain; charset=US-ASCII On 29 Oct 2010 at 21:14, Johnny Billquist wrote: So, your definition ties virtual memory into multi-user access? That's not the way I learned it. Consider (again folks, I'm sorry for the reference) the CDC 6600 (circa 1964). Every user is given a relocation address (called RA) and field length (FL) as a way of partitioning main memory. Each user's memory addressing space is kept isolated from every other's and this fits your definiton because one user's location X was different from every other user's location X and there was no way for a user to tell what his RA was; i.e. each user was safely "boxed in". That's not virtual memory by any stretch of the definition. Over- committing memory meant writing/reading the entire FL of a user to disk ("rollout" and "rollin"). Now consider the STAR-100 (I think it would qualify as the first virtual memory machine of CDC), circa 1969. Every user got an addressing space of 48 bits, but the machine itself had only 512Kwords (64 bit) of physical storage. For production use, most of the time the system was run in single-user mode (kept thrashing down with large data sets). That fits my definition of VM because the user was fooled into thinking that there was more physical memory than there really was. Aside from expanding program storage, the large addressing space was used to map file space (another type of "memory-mapped I/O"), so file access was actually performed through the paging hardware/software. That was kind of cool, as the STAR was a memory-to-memory vector machine, so you could use vector instructions on entire files, rather than have to issue reads and writes for pieces of a file. So I think we differ considerably in our definitions. --Chuck ------------------------------ Message: 2 Date: Sat, 30 Oct 2010 10:21:07 -0700 From: "Chuck Guzis" <cclist at sydex.com> Subject: Re: TTL HEX LED driver chip To: "General Discussion: On-Topic and Off-Topic Posts" <cctalk at classiccmp.org> Message-ID: <4CCBF193.19364.2603DF at cclist.sydex.com> Content-Type: text/plain; charset=US-ASCII On the same topic here, can anyone interpret the "state table" on the second page of the National DM74LS447 7-segment decoder datasheet? http://pdf1.alldatasheet.com/datasheet- pdf/view/149198/NSC/DM74LS447N.html I tend to think of state diagrams as belonging to things such as counters and don't have a clue as to what to make of the one furnished. --Chuck ------------------------------ Message: 3 Date: Sat, 30 Oct 2010 20:05:06 +0200 From: Fred Jan Kraan <fjkraan at xs4all.nl> Subject: Re: TRS-80 Model II Manuals To: cctech at classiccmp.org Message-ID: <4CCC5E52.9000802 at xs4all.nl> Content-Type: text/plain; charset=ISO-8859-1; format=flowed Thanks to the ever-useful JP Hindin, I've obtained a set of TRS-DOS See http://electrickery.xs4all.nl/comp/mirror/trs-80_archives/Manuals/Hardware/…. The Shugart stuff should be included. Essential this is from a modified copy of the files that were available from http://www.trs-80.com/ (copied without permission). Success, Fred Jan P.S. My own adventures with the Model II: http://www.xs4all.nl/~fjkraan/comp/trs80m2/ ------------------------------ Message: 4 Date: Sat, 30 Oct 2010 19:35:32 +0100 From: Philip Pemberton <classiccmp at philpem.me.uk> Subject: Re: DiscFerret: First working hardware, firmware and microcode! To: General Discussion: On-Topic and Off-Topic Posts <cctalk at classiccmp.org> Message-ID: <4CCC6574.8010103 at philpem.me.uk> Content-Type: text/plain; charset=UTF-8; format=flowed On 30/10/10 17:26, Al Kossow wrote: I almost mistook that for a floppy drive until I looked it up on Bitsavers...! I can't see any real reason why SA1000 support couldn't be added to the bridge-board. Looks like the only changes required would be: - An oscillator to generate the 3.6866us +/- 0.1% timing clock (270982 to 271524Hz, nominal 271253Hz). Although I have no idea what standard crystal frequencies could be used to generate that signal. The FPGA's PLL might be persuaded to do it, though, I'll have to check. - Two jumpers to disconnect the Timing Clock from the ST412/506 Data connector when these are not in use (or maybe just a second connector?) - A 50-pin connector for the SA1000 control cable The extra cost probably isn't worth worrying about... though I might have to restrict drive selection to Drive 0 only in order to get enough I/O pins for head selection. Thanks, -- Phil. classiccmp at philpem.me.uk http://www.philpem.me.uk/ ------------------------------ Message: 5 Date: Sat, 30 Oct 2010 19:47:54 +0100 (BST) From: ard at p850ug1.demon.co.uk (Tony Duell) Subject: Re: TRS-80 Model II Manuals To: cctalk at classiccmp.org Message-ID: <m1PCGTE-000J3xC at p850ug1> Content-Type: text/plain ...And if they;'re not, it's most likelyto be the drive belt. Yes I know 'up to speed' wasn't meant to be taken literally, but that seemed too good to miss :-) More seriously, what model of Shugart8" drive? Are there not manuals for them on bitsavers? -tony ------------------------------ Message: 6 Date: Sat, 30 Oct 2010 11:55:03 -0700 From: "Chuck Guzis" <cclist at sydex.com> Subject: Re: TRS-80 Model II Manuals To: "General Discussion: On-Topic and Off-Topic Posts" <cctalk at classiccmp.org> Message-ID: <4CCC0797.19723.7C011E at cclist.sydex.com> Content-Type: text/plain; charset=US-ASCII On 30 Oct 2010 at 19:47, Tony Duell wrote: Well, he could have a 220V 50Hz model and be running it on 120V 60Hz (the motor will develop sufficient torque to spin the disk). I've made that mistake once. The results from the reverse would be "interesting"... --Chuck ------------------------------ Message: 7 Date: Sat, 30 Oct 2010 15:29:06 -0400 From: Dave McGuire <mcguire at neurotica.com> Subject: Re: DiscFerret: First working hardware, firmware and microcode! To: General Discussion: On-Topic and Off-Topic Posts <cctalk at classiccmp.org> Message-ID: <4CCC7202.6050705 at neurotica.com> Content-Type: text/plain; charset=UTF-8; format=flowed On 10/30/10 2:35 PM, Philip Pemberton wrote: You could stick a little AD9833 (or similar) DDS chip on there. It's overkill, but they're pretty cheap now, and you'll get the desired frequency spot-on. -Dave -- Dave McGuire Port Charlotte, FL ------------------------------ Message: 8 Date: Sat, 30 Oct 2010 15:34:25 -0400 From: Dave McGuire <mcguire at neurotica.com> Subject: Re: Happy Birthday VAX 11/780 (influence of) To: General Discussion: On-Topic and Off-Topic Posts <cctalk at classiccmp.org> Message-ID: <4CCC7341.1090704 at neurotica.com> Content-Type: text/plain; charset=ISO-8859-1; format=flowed On 10/30/10 1:08 PM, Chuck Guzis wrote: That functionality is in use all over the place today as mmap(), accessing files as if they were memory, pushing the read/write burden out into the VM system. It's extremely effective. I'd not consider it to be "memory-mapped I/O" at all, though, in the context of "a processor reading and writing I/O ports". Sure, file I/O is a sort of I/O, and mmap() and similar techniques map that file I/O into the address space, but the context of this discussion...and indeed, most, it not all use of the term "memory-mapped I/O" doesn't refer to this sort of thing. -Dave -- Dave McGuire Port Charlotte, FL ------------------------------ Message: 9 Date: Sat, 30 Oct 2010 20:58:46 +0100 From: Philip Pemberton <classiccmp at philpem.me.uk> Subject: Re: DiscFerret: First working hardware, firmware and microcode! To: General Discussion: On-Topic and Off-Topic Posts <cctalk at classiccmp.org> Message-ID: <4CCC78F6.9040004 at philpem.me.uk> Content-Type: text/plain; charset=UTF-8; format=flowed On 30/10/10 20:29, Dave McGuire wrote: ?8.25 each with no quantity discount is *not* cheap. The FPGA only costs a few quid more than that. Digikey have them for ?5.86, but that's still more than a crystal. I wonder how the host adapters for the SA1000s generated this clock frequency... it does seem somewhat odd. The other thing is, I'd be concerned about releasing hardware with SA1000 support without testing it on an actual drive. I'm willing to bet the chances of me finding a working SA1000 in 230V/50Hz configuration are somewhere between 'slim' and 'nil'. I'll guarantee ST506 support though, given that I've got an ST277R RLL drive and controller here. Just need an MFM controller for it, or the RLL code tables for the Seagate ST21R or ST22R controller (which IIRC uses an Adaptec AIC010 chip)... -- Phil. classiccmp at philpem.me.uk http://www.philpem.me.uk/ ------------------------------ Message: 10 Date: Sat, 30 Oct 2010 13:23:00 -0700 From: Brent Hilpert <hilpert at cs.ubc.ca> Subject: Re: TTL HEX LED driver chip To: "General Discussion: On-Topic and Off-Topic Posts" <cctalk at classiccmp.org> Message-ID: <8534ab06c8e0281a7fcfc54d6a70efa5 at cs.ubc.ca> Content-Type: text/plain; charset=US-ASCII; format=flowed On 2010 Oct 30, at 10:21 AM, Chuck Guzis wrote: It's obviously a state diagram for a decade counter, my guess is someone just screwed up making the datasheet and included the state diagram from some other device. ------------------------------ Message: 11 Date: Sat, 30 Oct 2010 13:36:50 -0700 From: Brent Hilpert <hilpert at cs.ubc.ca> Subject: Re: Happy Birthday VAX 11/780 (influence of) To: "General Discussion: On-Topic and Off-Topic Posts" <cctalk at classiccmp.org> Message-ID: <d40186fd9ded72a101d654d9516da0f5 at cs.ubc.ca> Content-Type: text/plain; charset=US-ASCII; format=flowed On 2010 Oct 30, at 12:34 PM, Dave McGuire wrote: I remember in the 80's (programming primarily on BSD (and VMS)) thinking it would nice to have that functionality, how easy it would make a lot of file-access programming, and that it would be easy to add on a VM system. Of course, I was in ignorance of the prior histories such as the STAR that Chuck mentions. A few years later a friend would tell me about the new mmap function in unix. Well, Chuck did say "a type of". If files are a form of abstracted disk I/O, then mmap is a form of abstracted memory-mapped I/O. ------------------------------ Message: 12 Date: Sat, 30 Oct 2010 13:36:53 -0700 (PDT) From: Bob Rosenbloom <bobalan at sbcglobal.net> Subject: Fall cleaning, some small machines for free To: "General Discussion: On-Topic and Off-Topic Posts" <cctalk at classiccmp.org> Message-ID: <960487.42595.qm at web80502.mail.mud.yahoo.com> Content-Type: text/plain; charset=us-ascii Fall cleaning! I have a bunch of old computers and some peripherals. Most are not tested and I expect they may need some work to become operational, though some may work correctly as-is. Anyway, I'm hoping to find people interested in restoring these systems. There are three Burroughs B25 systems, each has a processor box, disk box, monitor, keyboard, and power supply. There is one box of docs and diskettes and one, very dirty, printer. http://www.anifur.com/clist/misc-b1.jpg http://www.anifur.com/clist/misc-b2.jpg http://www.anifur.com/clist/misc-b3.jpg http://www.anifur.com/clist/misc-b4.jpg IBM convertible, an early laptop type system. A Computer Products portable, thermal, serial terminal. http://www.anifur.com/clist/misc-ptr.jpg A Radio Shack TRS-80 model I with expansion chassis and monitor. I believe this has a bad power supply. http://www.anifur.com/clist/misc-rs.jpg A NEC Spinwriter terminal. This is like a Diablo daisywheel terminal except the print element is a cylinder. I know this one needs work but does power up. http://www.anifur.com/clist/misc-spin.jpg Some kind of cartridge tape system. I think it's SCSI interfaced. I don't believe this has ever been used. http://www.anifur.com/clist/misc-tape.jpg A large flatbed scanner that I also believe is unused. It's SCSI interfaced. UMAX 3000. http://www.anifur.com/clist/misc-scanner.jpg Digitech RS-232 analyzer with manuals. This runs CP/M 86 but I don't have the boot disc for it. Does power up. http://www.anifur.com/clist/misc-anal.jpg Kaypro 2, powers up and ask for a system disk. http://www.anifur.com/clist/kaypro1.jpg Hitachi pen plotter. This has a parallel interface. It powers up and works from the front panel. Light weight. http://www.anifur.com/clist/hitachi1.jpg Panasonic NV-A960 VCR editing unit. http://www.anifur.com/clist/a960-1.jpg Nicolet Zeta 8A pen plotter. 8 pens. Also powers up and works from the front panel. Serial interface. All of these are located in the Santa Cruz, CA mountains, near the Bonny Doon airport. I can possibly bring something into Santa Clara where I work. Best to come visit and check them out here. I really don't want to ship anything as I just don't have the time or energy. Please rescue these before I scrap them, I really need the space and these are now outside, but covered under a Quonset hut. Bob ------------------------------ Message: 13 Date: Sat, 30 Oct 2010 13:39:13 -0700 From: "Chuck Guzis" <cclist at sydex.com> Subject: Re: DiscFerret: First working hardware, firmware and microcode! To: "General Discussion: On-Topic and Off-Topic Posts" <cctalk at classiccmp.org> Message-ID: <4CCC2001.27472.DB6112 at cclist.sydex.com> Content-Type: text/plain; charset=US-ASCII On 30 Oct 2010 at 15:29, Dave McGuire wrote: Also, aren't the read/write data signals on the SA1000 differential? Or do I have them confused with the ST506 interface? --Chuck ------------------------------ Message: 14 Date: Sat, 30 Oct 2010 13:52:12 -0700 From: alan canning <scanning.cc at gmail.com> Subject: Need to find parts 82S23 / 74S188 To: "General Discussion: On-Topic and Off-Topic Posts" <cctalk at classiccmp.org> Message-ID: <AANLkTinzHd-NW1yL2LFuNG1=1q7s3hKOdxe2VLr7uXLH at mail.gmail.com> Content-Type: text/plain; charset=ISO-8859-1 Anybody no where to score some Sig 82S23 / Nat 74S188 parts ? I've tried all the usual suspects ( Ebay, local parts houses, Digikey, etc. ) with no joy. I believe this part was used on old S100 boards. Part also known as ( a.k.a. ) Fu 7111, AMD 27S18, MMI 6330, TI 18SA30 and Harris 7602. Need this part to fix an old computer controlled RF Power amplifier. Thanks for any and all help. Best regards, Steven ------------------------------ Message: 15 Date: Sat, 30 Oct 2010 13:54:40 -0700 From: "Chuck Guzis" <cclist at sydex.com> Subject: Re: Happy Birthday VAX 11/780 (influence of) To: "General Discussion: On-Topic and Off-Topic Posts" <cctalk at classiccmp.org> Message-ID: <4CCC23A0.9876.E985BD at cclist.sydex.com> Content-Type: text/plain; charset=ISO-8859-1 On 30 Oct 2010 at 15:34, Dave McGuire wrote: I'm sure and I'd never seriously call it "memory-mapped I/O"--but sometimes our world seems akin to that of Humpty-Dumpty: "When I use a word it means just what I choose it to mean--neither more nor less" Uh-oh, here comes another story... After I left CDC and the STAR project in 1977, my past came back to haunt me in the form of doing an optimizing FORTRAN for the ETA-10 in about 1983. We got a leased-line linkup to ETA in St. Paul and I asked what text editor they were using. Much to my surprise, it turned out to be the same editor I'd written for a lark around 1975 when the STAR had lots of really interesting byte string instructions and I could exploit file-mapped I/O to use them. Mind you, this was in the day of 16-line 1200 bps terminals. But the ETA-10 had none of those instructions, essentially having evolved out of the "everything but the kitchen sink CISC" state of mind of the original architecture. Some programmer had been detailed off to replace all of those cool vector instructions with their scalar equivalents! I was stunned and opined that with that way of thinking, the software end of the ETA project was doomed. --Chuck ------------------------------ Message: 16 Date: Sat, 30 Oct 2010 21:58:20 +0100 From: Philip Pemberton <classiccmp at philpem.me.uk> Subject: Re: DiscFerret: First working hardware, firmware and microcode! To: General Discussion: On-Topic and Off-Topic Posts <cctalk at classiccmp.org> Message-ID: <4CCC86EC.8040906 at philpem.me.uk> Content-Type: text/plain; charset=ISO-8859-1; format=flowed On 30/10/10 21:39, Chuck Guzis wrote: They're both differential. It's just that the SA1000 expects you to feed it a reference clock signal. It doesn't have to be locked against write-data, it just has to be there, and be accurate to 0.1%... Assuming the OEM manual is accurate, of course. -- Phil. classiccmp at philpem.me.uk http://www.philpem.me.uk/ ------------------------------ Message: 17 Date: Sat, 30 Oct 2010 21:23:40 +0100 (BST) From: ard at p850ug1.demon.co.uk (Tony Duell) Subject: Re: TTL HEX LED driver chip To: cctalk at classiccmp.org Message-ID: <m1PCHxn-000J3xC at p850ug1> Content-Type: text/plain Yes, I should have remembered that... Been there, done that :-) Of course. For 'b' you mmed the 'e' segment without the 'a' segment. That's what distinguishes it from '6' while my original question didn't preclude the use of discrete components, and while I happly ageee that the odd diodes, pull-up resisotrs, etc can lead to interesting solutions, I do feel that such a diode matrix is outisde the spirit of the problem. After all, you could say it can be solved with no ICs at all, just lots of discrete transistors, etc. :-) -tony ------------------------------ Message: 18 Date: Sat, 30 Oct 2010 21:27:54 +0100 (BST) From: ard at p850ug1.demon.co.uk (Tony Duell) Subject: Re: Nuclear Data ND 6600 To: cctalk at classiccmp.org Message-ID: <m1PCI1t-000J3yC at p850ug1> Content-Type: text/plain I am suprised there wasn't the standard driver circuits for the CRT (from composite vidoe, say). My guess is that there should have been, and they were msising. ICL did something similar. They had 'terminals' that consisted of encoded keyboards and composite monitors. The case was painted a horrible orange colour ... I think I still have one of the keyboards somewhere, but I mangaged to give the monitor away some years ago (thankfully...) -tony ------------------------------ Message: 19 Date: Sat, 30 Oct 2010 22:07:02 +0100 (BST) From: ard at p850ug1.demon.co.uk (Tony Duell) Subject: Re: TRS-80 Model II Manuals To: cctalk at classiccmp.org Message-ID: <m1PCIdm-000J4HC at p850ug1> Content-Type: text/plain Actaully, a lot of the 8" drives I have have 120V motors, but of course the right pulleys for 50Hz mains. They are run from an (auto)transformer, often the primary winding of the syatem mains transformer. So I suppose he could have something like that :-) -tony ------------------------------ Message: 20 Date: Sat, 30 Oct 2010 21:41:27 +0100 (BST) From: ard at p850ug1.demon.co.uk (Tony Duell) Subject: Re: TTL HEX LED driver chip To: cctalk at classiccmp.org Message-ID: <m1PCIF1-000J48C at p850ug1> Content-Type: text/plain Err, no. That's what the extra inverter is for. You know hos to use a 2^n input mux to make an arbitrary combinartorial function of n signals. Feed the n signals to the select inputs of the multiplexer and wire the 'data' inputs high or low as the truth table requires. But you can also yuse a 2^(n-1) input mux and maybe a single inverte, you connect n-1 of the input lines to the select inputs of the mux. And then for each of those combinations you consider the 2 truth table lines that apply (the last input, the one you've not used yet, of course distinguishes between the 2 lines in each pair). There are 4 possibilites : a) The output of the function is 0 in both cases (it doesn't depend on the last input at all) --> wire that input of thr mux to ground b) It's 1 in both cases -> wire the input to Vcc c) It's 0, 1 , it follows the last input in this case -> Wire that last input signal to the appropraite input of the multiplexer d) It's 1,0, it's the opposite of the last input. This is when you need that inverter. Invert the last input signal and wire the appropriate multiplexer input to the ouptu of the inverter. If oyu requre several functions of the same inputs (as here), you only need 1 ivnerter (assumeing there are no fan-out problems), since it's always thge same singal (say the 2^0 data input) you need to invert. Son yes, you can use 8 input multiplexers here (and 4 input ones if you only want to generate 6 or 8 patterns). Now, another silly aside... If you want to use a 2^(n-2) mux, you may need any or all of the 16 possible functions of the last 2 inputs (you split up the truth table into sets of 4 lines, and see which function of the last 2 inputs gives the right paattern, of course). This makes it less useful :-). But it's made me think pof a chip that AFAIK never existed... If you think of those 16 possible functions of 2 inputs, then 4 of them are 'trivial' in the sense that you can produce them with no logic at all. Namely 'always 0', 'always 1', 'equal to the A input' and 'equal to the B input'. Which leaves 12 non-rtrivial ones/ Now that means there could have been a 16 pin IC with 2 power pins, 2 inputs and 12 outputs, the 12 non-trivial functions of the 2 inputs. Use that witha 74150 for an arbitrary fucntion of 6 inputs... -tony ------------------------------ Message: 21 Date: Sat, 30 Oct 2010 21:44:22 +0100 (BST) From: ard at p850ug1.demon.co.uk (Tony Duell) Subject: Re: TTL HEX LED driver chip To: cctalk at classiccmp.org Message-ID: <m1PCIHq-000J49C at p850ug1> Content-Type: text/plain Absolutely. Of cousre I've kept all my old paper databooks, and still read them from time to tieme. Yes, it's very useful being able to get data on just about any standard IC over the internet. But it's useful in a different way being able to flip through a data book, see what's available, etc. I've yet to find a manufacturer's site that lets me browse in the same way. -tony ------------------------------ Message: 22 Date: Sat, 30 Oct 2010 21:48:01 +0100 (BST) From: ard at p850ug1.demon.co.uk (Tony Duell) Subject: Re: Wanted : Monitor Capable of TTL RGB To: cctalk at classiccmp.org Message-ID: <m1PCILO-000J4AC at p850ug1> Content-Type: text/plain Is CM8833 a TTL-input monitor? I think it was available as an option, but most of them take analogue RGB on the SCART socket. Most of the time the SCART inputs, for all they're supposed to be 1V will stand TTL (the CM8833 ones certainly will). Or since they're terminated to ground through a 75 ohm resistor, connect a 300 Ohm (or so) resistor in series with each TTL signal. Done that many times :-) Is there any reason a TV with a SCART socket isn't suitable? Most, if not all, LCD and plasma TVs should haev RGB inputs on the SCART socket, for example. -tony ------------------------------ Message: 23 Date: Sat, 30 Oct 2010 21:52:09 +0100 (BST) From: ard at p850ug1.demon.co.uk (Tony Duell) Subject: Re: I/O models (was RE: Happy Birthday VAX 11/780 (influence of)) To: cctalk at classiccmp.org Message-ID: <m1PCIPM-000J4BC at p850ug1> Content-Type: text/plain The obvious problem would be if the memroy map is already totally full. If you've got a Z80 systme with 64K of memory, it would be perverse to try memory mapped I/O (you could have some kind of MMU, but why...). Similarky trying to emmeroy map any kind of I/O on a 2MByte PERQ would be an 'interesting' exercise... -tony ------------------------------ Message: 24 Date: Sat, 30 Oct 2010 14:09:44 -0700 From: Brent Hilpert <hilpert at cs.ubc.ca> Subject: Re: Fall cleaning, some small machines for free To: "General Discussion: On-Topic and Off-Topic Posts" <cctalk at classiccmp.org> Message-ID: <981998b8f30737dece941bd3fc38a0c1 at cs.ubc.ca> Content-Type: text/plain; charset=US-ASCII; format=flowed On 2010 Oct 30, at 1:36 PM, Bob Rosenbloom wrote: I dismantled one of these a few years ago, it contained an (NEC-branded) 8080, a whack of NEC 8255's (PIO), half-a dozen ceramic Fujitsu MB8516's (2K*8 EPROMS, 2716-like), all socketed, for anyone that might take an interest in such stuff. ------------------------------ Message: 25 Date: Sat, 30 Oct 2010 15:11:06 -0600 From: ben <bfranchuk at jetnet.ab.ca> Subject: Re: Need to find parts 82S23 / 74S188 To: General Discussion: On-Topic and Off-Topic Posts <cctalk at classiccmp.org> Message-ID: <4CCC89EA.1000405 at jetnet.ab.ca> Content-Type: text/plain; charset=ISO-8859-1; format=flowed looks for 74S188 with google http://www.futurlec.com/Memory/74S188pr.shtml ------------------------------ Message: 26 Date: Sat, 30 Oct 2010 14:17:16 -0700 From: Geoffrey Reed <geoffr at zipcon.net> Subject: Re: TRS-80 Model II Manuals To: cctalk <cctalk at classiccmp.org> Message-ID: <C8F1D96C.2E65E%geoffr at zipcon.net> Content-Type: text/plain; charset="US-ASCII" Y'all are making me miss my tandy model 16 and 6000. ------------------------------ Message: 27 Date: Sat, 30 Oct 2010 22:21:08 +0100 (BST) From: ard at p850ug1.demon.co.uk (Tony Duell) Subject: Re: Need to find parts 82S23 / 74S188 To: cctalk at classiccmp.org Message-ID: <m1PCIrQ-000J3xC at p850ug1> Content-Type: text/plain IIRC, this is a PROM, 32*8 I think. Do you have a copy of the data to program into it? A blank chip is not a lot of use to you otherwise... Also while all the derives you've mentioned are I think compatible when being read (that is, as they are normally used in the circuit), the programming algorithms are different for differnet manufacturers. You need to get one that your programmer can handle -tony ------------------------------ Message: 28 Date: Sat, 30 Oct 2010 14:18:38 -0700 From: "Chuck Guzis" <cclist at sydex.com> Subject: Re: Need to find parts 82S23 / 74S188 To: "General Discussion: On-Topic and Off-Topic Posts" <cctalk at classiccmp.org> Message-ID: <4CCC293E.2099.FF7864 at cclist.sydex.com> Content-Type: text/plain; charset=US-ASCII On 30 Oct 2010 at 13:52, alan canning wrote: If you'd like something a bit closer to home, you might try ACP-- they're listing some IM5603s on eBay for $7.95 the each. --Chuck End of cctalk Digest, Vol 86, Issue 68 **************************************