test-drb February 2008

test-drb@ccmp.vtda.org

236 participants
373 discussions

Digitalker, SP0256, and SC-01 speech chips

by cclist＠sydex.com

> Date: Fri, 15 Feb 2008 13:37:46 -0800 > From: Brent Hilpert > Reading the Osborne book some time ago I got the impression the SMS300 > might be considered the first (micro-)DSP. Extracts: > > "The SMS300 is described by its manufacturer as a "microcontroller" > rather than a "microprocessor". This distinction draws attention to the > very unique capabilities of the SMS300 which make it the most > remarkable device described in this book." > > "The SMS300 is designed to serve as a signal processor, operating > at very high speed. The SMS300 can handle applications of this type at > more than 10 times the speed of any other device described in this > book." > > "If yours is a high speed signal processing application, then give > the SMS300 serious consideration; otherwise, the SMS300 is probably not > for you." It's true that the SMS300/8X300 was pretty fast for the time (instruction time was 250 nsec., consisting of 4 cycles of 62.5 nsec), the instruction set was very limited, as was the data addressing (256 bytes each for right and left I/O register banks). As to the limits of the implementation, consider the benchmark implementation in the Osborne book. If I had to guess, I'd say that where the 8x300 saw most of its application was in hard disk controllers. About the only other alternative in the day was to employ bit-slice logic or discrete TTL. I suppose I'd characterize the 8x300 as being halfway between bit- slice such as 2901 and a full-blown microprocessor like an 8080. Since this was a Harvard-architecture design, one way to extend the instruction set was to add additional bits onto the normally 16-bit wide instruction store and use them to implement additional functions. The limit of addressability of the instruction store was 8192 words. In fact, the 8x305 couldn't support its own development system. The SDK was initially offered as a board that could be plugged into the GI GIMINI CP1600 development system. Later, Signetics bundled the 8X305 as a signle-board SDK using an Intel 8035 to handle user interface functions. Cheers, Chuck

16 years, 4 months

Computer in 1900

by cclist＠sydex.com

> From: "Gavin Melville" > I had looked at relays, and while there certainly were relays in 1900, I > doubt they were very good in terms of bounce, actuation time etc. The > building where I work has an Otis made lift dating from 1980, done > completely with relays. It's fairly unreliable, and a lot of the relays > have to be fiddled with springs, copper disks, iron slugs etc. (Some of > them were designed that way, and some just needed it to make them work). As a counter-example, consider the Panama Canal, opened in 1914. All- electric run from a central control pulpit. With control circuitry designed by Edward Schildhauer, the equipment is still in service today, though it's due to be replaced. Relays and primitive servo motors were part of the whole affair. (BTW, some 1,500 electric motors are involved in the operation. I recall seeing a photo of some of the control circuitry--brass and varnished wood. It was a thing of beauty.) Cheers, Chuck

16 years, 4 months

RFC: Floppy reader/writer project (recovering UniPlus Unix for the Lisa)

by aek＠bitsavers.org

> Any chance someone else on this list has a copy of UniPlus Unix? printf(" UniSoft Corporation\n"); printf(" LISA UniPlus+ Serialization Program\n\n"); start: printf("Do you want to make a boot diskette (serialize)?\n"); printf("('y' or 'n') ");

16 years, 4 months

EPROM programmer

by brain＠jbrain.com

It appears I've staved off buying one of these too long and now I need one. Way back in the day, I used an ART EPP1, and I liked the serial connection (as I could use it from any machine,not just a PC). But, there are lots of options today. My primary interest is in replicating CBM KERNAL roms, though I would not mind uC programming capabilities. What do other people use for eprom programming? I see a slew of Willem programmers, but I don't understand why there are so many variants. A bummer is that they all use the Paallel Port, as far as I can tell. Jim

16 years, 4 months

FS: LD-V1000

by renagade13＠roadrunner.com

The message I found is old but I was wonderig if you still had any LD-V1000 laser disk players available. If so please send me an email with price. Thanks.

16 years, 4 months

EPROM programmer

by jack.rubin＠ameritech.net

> Date: Thu, 14 Feb 2008 16:02:24 -0600 > From: Jim Brain <brain at jbrain.com> > Subject: EPROM programmer > To: Classic Computer Talk <cctalk at classiccmp.org> > Message-ID: <47B4BA70.9080703 at jbrain.com> > Content-Type: text/plain; charset=ISO-8859-1; format=flowed > What do other people use for eprom programming? I see a slew > of Willem > programmers, but I don't understand why there are so many > variants. A > bummer is that they all use the Paallel Port, as far as I can tell. > > Jim > I ended up getting the True-USB Willem programmer(GQ-3X) Pack PRO from MCUMall and am quite happy with it. Service and support has been pretty good. Not Data I/O by any means but seems to be a pretty good value. USB interface is very convenient. http://www.mcumall.com/comersus/store/comersus_dynamicIndex.asp Jack No virus found in this outgoing message. Checked by AVG Free Edition. Version: 7.5.516 / Virus Database: 269.20.5/1278 - Release Date: 2/14/2008 10:28 AM

16 years, 4 months

DEC BA440/H7874 Power Bus Connector

by bob＠jfcl.com

Does anybody know if it's possible to interconnect the modular plug style power control bus used on the BA440/H7874 with the older three wire power control bus used on the "traditional" DEC 874/861 power controllers? If it is, does anyone have the pinout for the connecting cable? Thanks, Bob Armstrong

16 years, 4 months

Digitalker, SP0256, and SC-01 speech chips

by cclist＠sydex.com

> Date: Fri, 15 Feb 2008 12:54:01 -0500 > From: Dave McGuire > > As one who has had the extreme displeasure of programming both the > > 8X300 and an 8X305, > > Are they really that bad? How so? Brain-dead in the extreme, although the model might be interesting for the "1900 Computer" thread. You had 8 registers, a shifter and an ALU. R0 was the implied source for binary operations, but not implied as an accumulator. The instruction set was 8 instructions: 1. Move between the register file and the I/O bus 2. Add using R0 betweeen the register file and the I/O bus 3. AND as in (2) 4. XOR as in (2) 5. XMIT - a "Load Immediate" (8 bits to register file, but only 4 bits to I/O bus. 6. XEC - Execute instruction at the location formed by adding the 8- bit immediate field and the contents of a register. 7. NZT - replace the low order 8 bits (or 4 bits if I/O bus is being tested) of the program counter with a literal value if the specified register is nonzero. 8. JMP - unconditionally jump to the 13 bit immediate address. That's it. Thee were some strange conventions with the I/O registers, being designated as "right" and "left" bank which restricted their use in operations. There was one status flag-- overflow--addressable as regiser 8. No interrupts, unless you were fortunate enough to have an 8x310 ICC, which gave you a 4-level stack and 3 interrupts. The 8x310 also gave you some new instructions, implemented by decoding "do nothing" move instructions. You got a PUSH (current PC+2), a RETURN, SET and CLEAR interrupt mask and a clear pending interrupt status. You could use the 310 to implement a CALL by using a PUSH followed by a JMP. But 8x310s were rarely seen. By any measure, the PIC1640 was miles ahead in terms of ease of programming. AFAIK, the relay-based Mark I was the first Harvard architecture machine. Was the 8x300 the first microprocess (maybe too strong a word) to employ Harvard architure? I don't know, but it was an early design. It's interesting to me that, although the PIC claims to have Harvard architure, the model has been violated somewhat in the more advanced PICs. So, for example, members of the PIC18xx series allow for fetching of data values from program memory (TBL instruction) and modifying and re-flashing program memory under program control. Cheers, Chuck

16 years, 4 months

Is there a program to analyze a mag tape

by g-wright＠att.net

I a have a lot of mag tape/cartridge tape that I would like to analyze. I there a program that would write the whole tape then read it back, logging the retries and the errors. - Jerry Jerry Wright JLC inc g-wright at at.net

16 years, 4 months

Oldest operational computer

by cclist＠sydex.com

I think that many people are overlooking the matter of available techniques and materials in 1900 when supposing a computer operating in the Kops range was possible. No printed-circuitry; indeed, the mode of much electronic construction was busbar-type wiring on a varnished piece of wood. I don't know when enameled "magnet wire" came into production, but the standard for magnet wire for a long time was silk covering. Hookup wire may have been cotton or cambric, with gutta-percha for insulation. Resistors of any precision would likely have been wirewound. Does one need audions for amplification? Consider early telegraph repeaters or even chart recorders (running on a wind-up spring and recording microvolts). Even audio amplification could be achieved using compressed air. At the time, pneumatics were at a pretty high stage of development. Consider the workings of a player piano or pipe organ. But I think the technology that would have been selected in 1900 would have been mechanical or electro-mechanical. Consider, for example, the work of Leonardo Torres Quevedo. Cheers, Chuck

16 years, 4 months

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test-drb February 2008