test-drb November 2007

test-drb@ccmp.vtda.org

229 participants
508 discussions

by james＠attfield.co.uk

> Message: 24 > Date: Fri, 16 Nov 2007 08:57:12 -0500 > From: Allison <ajp166 at bellatlantic.net> > Subject: Re: Speaking of multiple processors... > To: cctech at classiccmp.org > Message-ID: <0JRL00BZ4QQMNPW2 at vms042.mailsrvcs.net> > Content-Type: text/plain; charset=iso-8859-1 > > >Cromemco also had Z80s on their I/O processor boards, and when > the later 680x0 > >CPU boards dropped the Z80 you could still run your Z80 programs > on the I/O card. > > > >mike > > This is not uncommon. > > H89 had two, one for the terminal and the other was the processor for > the computer. > > My NS*Horizon had two when I added the Teletek HDC(hard disk) as that > has a local z80. When I added a smart FDC of my own design and later > smart printer spooler and other IO with local cpu the nuber fo cpus grew. > > The Compupro system can easily have three, ZPB, Their mux board and > any of the hard disk controllers. I have one that has 68000, 8085 and > Z80 (maincpu, mux and Disk3). > > It's something that isn't unusual as it would seem. > > Allison Absolutey. I have a couple of IOP cards here complete with Z-80, Z80-SIO and firmware - very nice cards. Further, way back in the early '80s the Comart Communicator had an intelligent FDC sporting a Z-80 - formatting was just a matter of setting up the command and executing asynchronously, the host CPU could then go off and do something else. This was way ahead of the common-or-garden FDC's of the time, even Cromemco's FDC's at the time. A much under-rated system... Jim

17 years, 1 month

Speaking of multiple processors...

by ajp166＠bellatlantic.net

> >Subject: Re: Speaking of multiple processors... > From: M H Stein <dm561 at torfree.net> > Date: Fri, 16 Nov 2007 14:30:25 -0500 > To: "'cctalk at classiccmp.org'" <cctalk at classiccmp.org> > >---------Original Messages: >Date: Fri, 16 Nov 2007 08:57:12 -0500 >From: Allison <ajp166 at bellatlantic.net> >Subject: Re: Speaking of multiple processors... > >> From: M H Stein <dm561 at torfree.net> >> Date: Thu, 15 Nov 2007 11:29:05 -0500 > >>Cromemco also had Z80s on their I/O processor boards, and when the later 680x0 >>CPU boards dropped the Z80 you could still run your Z80 programs on the I/O card. >> >>mike > >This is not uncommon. > >H89 had two, one for the terminal and the other was the processor for >the computer. > >My NS*Horizon had two when I added the Teletek HDC(hard disk) as that >has a local z80. When I added a smart FDC of my own design and later >smart printer spooler and other IO with local cpu the nuber fo cpus grew. > >The Compupro system can easily have three, ZPB, Their mux board and >any of the hard disk controllers. I have one that has 68000, 8085 and >Z80 (maincpu, mux and Disk3). > >It's something that isn't unusual as it would seem. > >Allison > >----------Reply: >Well, I didn't say or imply that dual-CPUs like Cromemco's DPU and XPU or >intelligent I/O co-processors like their IOP and Octart were uncommon; in >fact I was just adding Cromemco to the list under discussion which ranged >from CDC big iron down to C-64s, and both C-64s and Cromemcos could >easily have 4 or 5 CPUs talking to each other one way or another. They were not alone doing that. >But now that you mention it, I did think what Cromemco did when their XXU >68010/20 CPU board finally dropped the Z80 _was_ a little unusual; although >the Z80 was gone from the processor board, your Z-80 CDOS or CP/M >application could still use the Z80 on the existing I/O board when it wasn't >handling I/O traffic. Did anyone else run *application* programs like a word >processor or spreadsheet (as opposed to applications like the C-64's disk >utilities) on an I/O co-processor board? I guess it could. Never messed with Cromemco but they had nice hardware. >And that's not quite the same either as e.g. an Apple or the SuperPet, which >effectively just used the main system as console and memory for an *added* >co-processor. > >Admittedly, at some point the distinctions do get a little blurred. Way fuzzy. Allison >m

17 years, 1 month

New acquisitions (PDP 11/40 DecDataSystem and 11/10)

by wacarder＠earthlink.net

This morning I moved some newly acquired PDP-11 items into my shop. Among the items were a beautiful PDP-11/40 DecDataSystem in a yellow / red color scheme along with a TU10, PC05, and RK05F, another standard PDP-11/40, a PDP-11/10 with a Laboratory Peripheral System, RX01, and TU60 DecCassette unit, and a pieces parts PDP-11/20. Also included in this shipment was an LA36 DecWriter II that has a phone handset modem unit. You can check out some pictures at: http://www.woffordwitch.com/PDP1140-DecDataSystem.asp http://www.woffordwitch.com/PDP1140-FourthOne.asp http://www.woffordwitch.com/PDP1110-2.asp http://www.woffordwitch.com/LPS-11.asp I have not done anything with these items besides move them into my shop. The 11/20 is in pieces in a box, and I have not evaluated the completeness of it yet. I did see the toggle switch front panel, but do not see the plexi that goes with it. I have the CPU box, but some boards are loose in another box. I need to take inventory to see exactly what I have. Ashley Carder http://www.woffordwitch.com

17 years, 1 month

dovebid: Onyx2 Reality Monster (Hazelwood, MO)

by legalize＠xmission.com

<http://www.dovebid.com/assets/display.asp?ItemID=cse2741> -- "The Direct3D Graphics Pipeline" -- DirectX 9 draft available for download <http://www.xmission.com/~legalize/book/download/index.html> Legalize Adulthood! <http://blogs.xmission.com/legalize/>

17 years, 1 month

Need HP75 Manual

by silent700＠gmail.com

Hi all - wondering if anyone has a scan of the manual for the HP75 portable computer. If not, I'd like to talk to anyone that has operated theirs with the card reader and can give me some help re: the command syntax? I've finally gotten a power supply for mine (thanks to the big junkpile at VCF!) and I have a whole stack of magstrips and no idea how to read them. I found a page with partial docs that allowed me to catalog a strip, but that's where I'm stuck. Thanks in advance -j -- silent700.blogspot.com Retrocomputing and collecting in the Chicago area: http://chiclassiccomp.org

17 years, 1 month

PDP by the pound

by tponsford＠rnsmte.com

HI All A friend mentioned to me he saw what looked to be some DEC equipment at a local scrap yard. Looking through the scrap I saw a really sad looking rack with some RA81 and 82's. They looked too damaged and too hard to dig out, but as I was leaving, out of the corner of my eye, I spied another "buried" cabinet with 8" floppy drives. Curiosity got the best of me and a closer look the cabinet said KEVEX 1600. The floppies looked to be in good condition so I removed the cover plate and lo and behold, a Qbus 11/03 greeted me! I yanked the third-party qbus chassis out and also the *" drive cabinet, which turned out to be a DSD 210! The scrap yard charged me by the pound, around $20! Cheers Tom Ponsford

17 years, 1 month

Fwd: 1979 CGI on PDP-11/70 w/Tektronix 4014

by legalize＠xmission.com

>From a friend of mine from Project DELTA. Watching Ralph do his thing with the Tektronix terminal is what kept me interested in programming and made me want to study computer graphics. Hi Guys, I finally got around to having some old Super-8 movies converted to QuickTime, and then posted them to YouTube. These show some wireframe computer graphics I developed in high school thanks to project Delta. A bit crude but bear in mind that it's 1979 and I didn't refer to any literature and wrote it all in Basic+2 spaghetti code ;-) Graphics shot directly from Tektronix display (stop-motion used to get animation effect) using high-speed B&W film. Note many of the scenes are stereoscopic: if you have a viewer you'll see the stereoscopic image or if you cross your eyes you will see the image with reverse perspective. http://www.youtube.com/watch?v=ue4Yo_a34XM Music video for Pink Floyd's "Welcome to the Machine". This is primarily pastel on paper, but there is a portion in the middle using printouts from the Tektronix display which I colorized by holding a match under the paper. There's also a shot of a Beehive (?) terminal at the end running a rasterized Game of Life. http://www.youtube.com/watch?v=IAfK1rL9fCw -Ralph -- Ralph Gonzalez ralphgonz at gmail.com -- "The Direct3D Graphics Pipeline" -- DirectX 9 draft available for download <http://www.xmission.com/~legalize/book/download/index.html> Legalize Adulthood! <http://blogs.xmission.com/legalize/>

17 years, 1 month

Tarbell is making me insane

by ajp166＠bellatlantic.net

> >Subject: Re: Tarbell is making me insane > From: ard at p850ug1.demon.co.uk (Tony Duell) > Date: Thu, 15 Nov 2007 20:50:34 +0000 (GMT) > To: cctalk at classiccmp.org > >> >This faster signal might be better for the disk drive? >> >> Potentially. Remember FM floppy recording was passe' by the early >> 80s with every one needed far greater space. It want even a >> consideration buy time PC 3.5" floppies hit the street. > >As I understand it, FM at 125bps has (only) pulse spacings that can occur >in MFM at 250kbps. The latter has some other spacing too, of course, but >the point is that unless you're trying to be awkward, it's impossible to >make a drive that will correctly handle any MFM data at 250kbps that will >not also correctly handle FM data at 125kbps. (About the only way you >could do it is if the drive tries to decode the data back to user bytes >and then re-encodes them onto the disk in a totally different way. I know >of know floppy drive that ever tried something like that!). > >There should be no problem at all in using a 3.5" DD floppy drive with >the FM data stream that uou'd have sent to an SA400. Doesn't completely work that way. If it were bandwidth only maybe. The problem is it's timing and that causes peak shifts that increase with jamming those bits in a more confined space (flux tranistions per inch) and that makes 3.5" track 000 an approximation of SA400L track 41ish. That doesnt' factor the lower S/S+N ratio of 135 tpi against 48TPI. Will it work, I may but if it doesn't work well it may not be broken. Reason is the DD FDCs (both 765 and 1793/2793) have additional hardware to add a timing shift based on pattern written and better feature extraction for read. This is not present on 1771 based boards. Allison >-tony

17 years, 1 month

Speaking of multiple processors...

by ajp166＠bellatlantic.net

> >Subject: Re: Speaking of multiple processors... > From: M H Stein <dm561 at torfree.net> > Date: Thu, 15 Nov 2007 11:29:05 -0500 > To: "'cctalk at classiccmp.org'" <cctalk at classiccmp.org> > >-----------Original Message: >Date: Thu, 15 Nov 2007 08:32:02 +0000 >From: Gordon JC Pearce <gordonjcp at gjcp.net> >Subject: Re: Speaking of multiple processors... > >On Thu, 2007-11-15 at 00:32 -0500, Roy J. Tellason wrote: >> Didn't that "Superbrain" computer use a couple of Z80 chips in there? IIRC, >> one was the "main" CPU and the other one handled I/O tasks of some sort >> (disk?). ><snip> > >It does. I believe one handles disk accesses, while the other does the >rest. Once I get mine working, I'll tell you more.<snip> > >Gordon > >----------Reply: >Cromemco also had Z80s on their I/O processor boards, and when the later 680x0 >CPU boards dropped the Z80 you could still run your Z80 programs on the I/O card. > >mike This is not uncommon. H89 had two, one for the terminal and the other was the processor for the computer. My NS*Horizon had two when I added the Teletek HDC(hard disk) as that has a local z80. When I added a smart FDC of my own design and later smart printer spooler and other IO with local cpu the nuber fo cpus grew. The Compupro system can easily have three, ZPB, Their mux board and any of the hard disk controllers. I have one that has 68000, 8085 and Z80 (maincpu, mux and Disk3). It's something that isn't unusual as it would seem. Allison

17 years, 1 month

BBC coverage: Colossus vs. Modern hardware

by rdawson16＠hotmail.com

> Date: Thu, 15 Nov 2007 19:14:48 -0500 > From: wdonzelli at gmail.com > To: cctalk at classiccmp.org > Subject: Re: BBC coverage: Colossus vs. Modern hardware > > > AFAIK there's no transmission equipment as part of the SZ42 itself though, so > > something would still need to be hooked between that and a giant aerial in > > order to do the transmission; I think it was this bit that Will was interested in. > > No, I am interested in the thing that modulates the bitstream, before > the transmitter. The modem, basically, not the transmitter. > > -- > Will Will, I did some fairly bizarre modem design for a downhole well logging camera, transmitting power and digital video over 5 miles of coax. I can probably answer any modulation questions you may have, or point you to the literature I used in my research and design. Randy _________________________________________________________________ Peek-a-boo FREE Tricks & Treats for You! http://www.reallivemoms.com?ocid=TXT_TAGHM&loc=us

17 years, 1 month

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test-drb November 2007