RE: Wanted: HP7970 hub mech

I didn't even know there was such a thing as a twist to tighten on the HP7970. On the 7970A maybe? Marc -Original Message- From: cctalk [mailto:cctalk-boun...@classiccmp.org] On Behalf Of Chuck Guzis via cctalk Sent: Sunday, November 19, 2017 7:32 PM To: CCtalk Subject: Wanted: HP7970

Re: Ideas for a simple, but somewhat extendable computer bus

If you ever look at how interrupts are implemented on STD bus, you'll run in fear. There are only two options, chain the slot to slot interrupt line (assuming all slots are filled downstream of the CPU) and share the one request signal - implementing any CPU-specific interrupt requirements

Re: Ideas for a simple, but somewhat extendable computer bus

On 11/19/2017 08:11 PM, Ken Seefried via cctalk wrote: > More importantly, the vast number of compatible I/O cards that were > produced. Much alternative history to be pondered. So we agree on parallel standard buses, that STD bus is a strong contender with varied processor base. There *is*

Re: Ideas for a simple, but somewhat extendable computer bus

I've always thought STD-Bus missed a real opportunity here. Small enough to be cost effective (relative to the size of, say, S-100 (bonus, no stupid power supply issues)), sane, flexible enough bus structure that I believe there are at least CPU cards using: - 4004/4040 (pre-standard?) -

Re: Ideas for a simple, but somewhat extendable computer bus

On Nov 19, 2017 7:18 PM, "allison via cctalk" wrote: The rest is the specific implementation. What happens if the CPU is 1802 or something else that does not match the 6500 or 8080z80 models. There is nothing that prevents either the serial or parallel arbitration

Re: Ideas for a simple, but somewhat extendable computer bus

On 11/19/2017 08:54 AM, Noel Chiappa via cctalk wrote: > > From: Allison > > > simple 16 data, 24 address likely 6 lines for basic control plus others > > your up to 50+ lines > > I would seriously consider shared data/address lines, like on the QBUS. It > doesn't add _that_ much

Wanted: HP7970 hub mech

This is a pretty far-fetched request, but here goes. The quick-release levers on the HP 7970 tape drive are plastic. They're starting to get brittle. I've got one that's showing cracks, so I swapped it the the one on the takeup reel, as that one doesn't see as much action as the one on the

Re: Ideas for a simple, but somewhat extendable computer bus

On 11/19/2017 03:43 PM, Eric Smith via cctalk wrote: > On Sat, Nov 18, 2017 at 10:48 PM, Jim Brain via cctalk < > cctalk@classiccmp.org> wrote: > >> Looking at the schematic for the ECB, I cannot find any description of the >> signals BAI, BAO, IEI, and IEO. Can anyone shed some light on the

Re: Looking for Silent 700 model 787 manual

On Sunday (11/19/2017 at 05:46PM -0800), Fred Cisin via cctalk wrote: > On Sun, 19 Nov 2017, Chris Elmquist via cctalk wrote: > >I recently acquired a TI Silent 700 model 787 terminal. This cc 1980 > >unit is an interesting member of the Silent 700 family as it is capable > >of 120 chars/sec

Re: Looking for Silent 700 model 787 manual

On Sun, 19 Nov 2017, Chris Elmquist via cctalk wrote: I recently acquired a TI Silent 700 model 787 terminal. This cc 1980 unit is an interesting member of the Silent 700 family as it is capable of 120 chars/sec printing and has an internal 300/1200 baud direct connect modem that does Bell 103,

Looking for Silent 700 model 787 manual

I recently acquired a TI Silent 700 model 787 terminal. This cc 1980 unit is an interesting member of the Silent 700 family as it is capable of 120 chars/sec printing and has an internal 300/1200 baud direct connect modem that does Bell 103, Bell 212A and Vadic modulation in both originate and

Re: LA30 parts and question

Hi all, an update on the sourcing questions below: > On Nov 11, 2017, at 5:53 PM, Fritz Mueller wrote: > > I noticed that a few of the thin steel ribbon springs in the paper path are > missing or broken on my unit, and some of the rubber bushings have hardened > and

Re: Ideas for a simple, but somewhat extendable computer bus

On 11/18/2017 5:57 PM, Eric Christopherson via cctalk wrote: On Fri, Nov 17, 2017, ben via cctalk wrote: On 11/17/2017 6:59 PM, Chuck Guzis via cctalk wrote: On 11/17/2017 05:34 PM, Jim Brain via cctalk wrote: It does not have to be fast.  I rather thought, "what is the simplest multi-cpu

Re: Slightly OT: Computer internals book recommendations

On 11/19/2017 12:29 AM, Huw Davies via cctalk wrote: On 19 Nov 2017, at 10:57, Eric Christopherson via cctalk wrote: Basically, I'm looking for a certain book (although really any book in the same vein would satisfy), which was on computer system architecture,

Re: Ideas for a simple, but somewhat extendable computer bus

On 11/19/2017 2:43 PM, Eric Smith wrote: Similarly for how the card deals with interrupts, but using the IEI and IEO as the daisy chain. Thanks for the context.  I think the fact that !BUSAK is present on A31 threw me

Re: Ideas for a simple, but somewhat extendable computer bus

On Sat, Nov 18, 2017 at 10:48 PM, Jim Brain via cctalk < cctalk@classiccmp.org> wrote: > Looking at the schematic for the ECB, I cannot find any description of the > signals BAI, BAO, IEI, and IEO. Can anyone shed some light on the function > of these signals? > Bus Acknowledge In and Out,

Re: Sync on Green RGB video

I have the same problem with a cheap 19" LCD VGA Screen. What i made is to seperate the required sync signal with an LM1881 Video Sync Seperator. I used the standard application from the TI datasheet.The only difference is that i used an viariable resistor on pin 6 to adjust to the Sync

Re: Sync on Green RGB video

On 11/18/2017 6:44 PM, william degnan wrote: On Nov 18, 2017 4:09 PM, "Douglas Taylor via cctech" > wrote: > > I have a couple of vaxes that output 'unique' video, Alpha 3000 300, Alpha 3000 400, Vax 4000 VLC, and Vax Station 3100 M76. >

Re: Ideas for a simple, but somewhat extendable computer bus

On 11/19/2017 9:08 AM, emanuel stiebler wrote: On 2017-11-18 23:48, Jim Brain wrote: > Looking at the schematic for the ECB, I cannot find any description of > the signals BAI, BAO, IEI, and IEO.  Can anyone shed some light on the > function of these signals? Here again:

Re: Slightly OT: Computer internals book recommendations

I have the second edition (there appears to now be a third out!) but re-reading the preface and "what's changed since the first edition" doesn't seem to say what I remembered re: buses (namely, it says nothing at all). It is possibly my professors were referring to a much earlier course/textbook

Re: Slightly OT: Computer internals book recommendations

> From: Sophie Haskins > earlier editions of "Computer Systems: A Programmers Perspective" had a > bunch of discussions of buses etc .. but the edition I have explicitly > calls out that they felt like it wasn't important to have chapters on > anymore :( Well, that might not

Re: Slightly OT: Computer internals book recommendations

I want to say that earlier editions of “Computer Systems: A Programmers Perspective” had a bunch of discussions of buses etc in addition to assembly, compilers, linking, etc. but the edition I have explicitly calls out that they felt like it wasn’t important to have chapters on anymore :( > On

Re: Ideas for a simple, but somewhat extendable computer bus

On 2017-11-18 23:48, Jim Brain wrote: > Looking at the schematic for the ECB, I cannot find any description of > the signals BAI, BAO, IEI, and IEO. Can anyone shed some light on the > function of these signals? Here again: https://en.wikipedia.org/wiki/Europe_Card_Bus I have some ECB

Re: Ideas for a simple, but somewhat extendable computer bus

> From: Allison > simple 16 data, 24 address likely 6 lines for basic control plus others > your up to 50+ lines I would seriously consider shared data/address lines, like on the QBUS. It doesn't add _that_ much complexity to share the lines (I did a slave device using only 74xxx