test-drb December 2001

test-drb@ccmp.vtda.org

243 participants
1096 discussions

by steven_j_robertson＠hotmail.com

> >Most of the cards in the machine you ahve are pretty good -- the >HS terminal will let you connect to a crt or a serial PC port with >a terminal emulator... > I did find a HP cable with a 24 pin card edge connector on one end and a 25 pin D connector on the other. The 25 pin connector only has a few pins in it (typical of HP serial cables) including 2, 3, 7, 13,and 25. I traced the wires back to where they would appear on the HS terminal card and it appear that I have the right cable for the box. At least I won't have to kludge togerther a cable. WhooHoo. I have plenty of dumb terminals laying around including a number of old HPs. So, based on your message, it sounds like I have everything necessary to make the computer "talk" to a terminal. >If you would like, I can send you a real short program >that you can key infrom the console that makes the >lights blink... This would be great! Another question: I'm assuming the placement of the cards in the cage determines the "Address" or LU of the card. Does it matter which slots the cards go in or is there an accepted standard for this? Which slot does the HS terminal card (console) go in? Thanks Again, SteveRob _________________________________________________________________ Get your FREE download of MSN Explorer at http://explorer.msn.com/intl.asp.

22 years, 9 months

URL for "The Wench Bench"

by CLeyson＠aol.com

Interenting topic. How the hell do you build electronics that survives 15000G ! Got any technical info on RF proximity fuses ? I read somewhere that they used the capacitance between shell nozecone and target to pull the osc off frequency, a bit like a Theramin. BTW, the Germans developed a remotely controlled TV guided bomb during WW2. Luckily for the allies the picture broke up as the bomb approached its target and development was stopped. Chris

22 years, 9 months

Solace 3.0

by frustum＠pacbell.net

Ho, Ho, Ho -- Just in time for Christmas, it's Solace 3.0. Free Sol's for everyone! This version of my Sol emulator fixes a few small bugs (including the fact that the last release broke the ability to save to virtual tapes in real-time mode). More importantly, it adds very low level emulation of a DS/DD Northstar disk system. You can run CP/M 2.2 as well as NSDOS. The emulator comes with a few virtual disk images, including a collection of Sol-relevant files culled from the CPMUG archives. Solace home page: http://www.thebattles.net/sol20/solace/solace.html Sol home page: http://www.thebattles.net/sol20/sol.html ----- Jim Battle == frustum(a)pacbell.net

22 years, 9 months

9-Tracks Drives, especially Overland Data

by healyzh＠aracnet.com

A while back I managed to get a nice little Overland Data OD5612 SCSI 9-Track tape drive. I'm looking into getting it put somewhere that I can actually use it should I want (well that and I needed the spot it was for a couple of S-Bus expansion chassis). Anyway I just noticed something. It's got a selector switch on it for 1600bpi and 6250bpi. Am I correct in assuming that this means that I can only read those two formats? Zane -- | Zane H. Healy | UNIX Systems Administrator | | healyzh(a)aracnet.com (primary) | OpenVMS Enthusiast | | | Classic Computer Collector | +----------------------------------+----------------------------+ | Empire of the Petal Throne and Traveller Role Playing, | | PDP-10 Emulation and Zane's Computer Museum. | | http://www.aracnet.com/~healyzh/ |

22 years, 9 months

6502/Z80 speed comparison (was MITS 2SIO serial chip?)

by pete＠dunnington.u-net.com

On Dec 22, 4:44, Ben Franchuk wrote: > Richard Erlacher wrote: > > > > Let's leave compilers out of the equation. Even the same small-C compiler, > > targeted at the two quite different CPU's potentially represent a significant > > skew in favor of one or another of the two. > > > How can you have skew? That is the whole idea of benchmark is to > compare > two machines. I would expect that the simple C that was given would be a > good test > when judged with other benchmarks. For a comparison of two development systems, maybe, but not for a simple comparison of processors. You'll find that the compilers were written differently for the different processors. As likely as not, one will be better at certain things than another, or better on one processor. For example, gcc does fairly poorly on a PDP-11 or an SGI machine (SGI's cc will run rings round gcc for MIPS in almost every respect) yet works very well on an x86 achitecture, because that's where the major development was done. If you take a compiler written for one chip, say a Z80, a straight port will produce poor code for a 6502 because you have to think about things in a different way, and this will be more apparent with a simple compiler than sophisticated one. -- Pete Peter Turnbull Network Manager University of York

22 years, 9 months

M8650 async board problem

by pete＠dunnington.u-net.com

On Dec 22, 23:15, Tony Duell wrote: > As the fault wasn't on the M8650, why did they cut that track? Did they > just never want interrupts? I've no idea. It wasn't cut by the previous owner; he doesn't know why either. > > However the fault, for those who're still reading, wasn't really the M8650 > > itself. There were two problems. At some point, I had unplugged the > > serial cable from the Berg connector, so there was noise on the serial > > input, which upset the diagnostics. The second problem was that the PSU > > And adding an 'antenna' (as in the serial cable) actually helps this? The proper cable has a jumper in the Berg connector to enable the EIA part of the circuit. It connects the 1489 output to the first gate in the receiver section. Without the jumper, the input to that gate floats, and hence picks up all sorts of noise. I wouldn't be surprised if I could pick Radio 2 up on that :-) > > +5V was down to about 4.5V, which isn't great for TTL. I'd checked the > > This has caught me so often when repairing DEC machines. The PSUs set up > fine on no-load and drop to 4V to 4.5V when loaded. And this causes the > most _amazing_ faults. Yes, and I should have known better. I realised something of the sort was amiss when I found that moving cards between front and rear backplanes made a difference. With everything in the front, the +5V went down to less than 4.3V. -- Pete Peter Turnbull Network Manager University of York

22 years, 9 months

X10 revived - looking for modules, switches, etc

by mythtech＠Mac.com

>Anyone have a stash of cheap excess modules, switches, etc for X10/BSR/etc. >I know people mentioned sometime ago that they have bought boxes full of >stuff for a few bucks but I don't have those same resources here and am >setting up an "easier way of life" for my 64 yr old mother in law that has >trouble getting around and forgets to turn lights off, falls asleep with the >TV on, etc. I have the 2 way module to the PC and a remote that she can use >but wall switches, appliance and lamp modules, etc are still needed. Email >me direct if you have excess and want to make space. We can either work a >cash deal or trade as I have lots of PS/2 equipment around and some older >IBM PC equipment I can trade with. Thanks in advance. I don't have any that is partable (I don't have much stuff right now at all, and the few things I do have are tied up in heavy use). But, I have found X10.com has cheap prices on packages, in many cases for just a few bucks, you can get a full setup, and they run specials on a regular basis that practically give stuff away. They have a newsletter for the specials, but they tend to send out emails TOO often, so use an email account you don't care about being spammed if you sign up (and I am fairly sure they passed my addy on to others... fortunatly, I NEVER sign up for those kinds of things except under certain accounts that are already heavly spammed) -chris <http://www.mythtech.net>

22 years, 9 months

6502/Z80 speed comparison (was MITS 2SIO serial chip?)

by ajp166＠bellatlantic.net

The most common reason for not using an hll is that unless the compiler is well written and optimizing you see the compiler not the cpu. Small C was a good language but the result was often so poor that even a small amount of hand optimization was easy to accomplish. For a cpu like 6502, this tended to be more true as many of the things the C language likes just dont map to cpu instruction set that directly. Same was true for most of the Z80 versions of small C as most treated it as an 8080 and didnt use the more useful instrucitons. As tot he PDP-11 that was the consumate C machine at the instruction set level. Allison -----Original Message----- From: Ben Franchuk <bfranchuk(a)jetnet.ab.ca> To: classiccmp(a)classiccmp.org <classiccmp(a)classiccmp.org> Date: Saturday, December 22, 2001 9:40 PM Subject: Re: 6502/Z80 speed comparison (was MITS 2SIO serial chip?) >Richard Erlacher wrote: >> >> Let's leave compilers out of the equation. Even the same small-C compiler, >> targeted at the two quite different CPU's potentially represent a significant >> skew in favor of one or another of the two. >> >> Dick >How can you have skew? That is the whole idea of benchmark is to >compare >two machines. I would expect that the simple C that was given would be a >good test >when judged with other benchmarks. The 8080/Z80/8086 all generate the >same poor >code. This surprised me as shows how poor the 16 bit intel product was. >The PDP-11 >version was rather nice but it even has a few quirks. >-- >Ben Franchuk --- Pre-historic Cpu's -- >www.jetnet.ab.ca/users/bfranchuk/index.html >PS. Note all my FPGA machines generate nice 'Small C' code and have a >resonably orthogonal instruction set. The well hacked Small C compiler >self compiles under >24 KB. A similar compiler for the 8080 is about 48KB.

22 years, 9 months

6502/Z80 speed comparison (was MITS 2SIO serial chip?)

by CLeyson＠aol.com

In a message dated 12/22/01 Chris Leyson writes: >> How about a straight insertion bubble sort ? A completely useless task but it >> does take a defined number of data moves and compare operations. The array >> to be sorted could be say, 16-bit signed integer, 1k words long and in reverse >> order. (That should take a while for a 6502 to sort out). In a reply dated 12/22/01 Richard Erlacher writes > Yes, maybe something of that sort would be appropriate. Testing it on 8-bit, > and then 16-bit quantities might be just the thing for testing the relative > ability, in spite of architectural differences, of handling longer data. I'd > suggest that larger records might be more appropriate, i.e. 32-byte records, > etc. OK 8-bit and 16-bit data is appropriate but would require separate algorithms. As for record length I would suggest at least 1k (1024) entries. (Eliminates base page cheating) > BTW, when I was in college, which I realize was some time ago, but, back then, > Bubble Sort and Insertion Sort were two different algorithms ... I don't > remember the differences, but will check my old texts, though they're in > Sanskrit ... Apologies, that should have read insertion sort OR bubble sort. Bubble sort runs through the array comparing adjacent values and swaps them whereas insertion sort moves an array member until it's in the right place. In terms of performance they are both slow algoritms. Here is the code from Numerical Recipies for an insertion sort (Fortran and C) Sorts an array arr(1:n) into ascending numerical order, by straight insertion. n is input; arr() is replaced on output by its sorted rearrangement. integer n real arr(n) integer i,j real a do j=2,n a=arr(j) do i=j-1,1,-1 if (arr(i).le.a) goto 10 arr(i+1)=arr(i) end do i=0 10 arr(i+1)=a end do { int i,j; float a; for (j=2;j<=n;j++) { a=arr[j]; i=j-1; while (i>0 && arr[i] > a ); arr[i+1] = arr[i]; i--; } arr[i=1]=a; } } Ignore the floats and reals for the data, they should be ints or chars for the purposes of our 6502/Z80 benchmark. Just for the hell of it, I will try this out in DSP56300 assembler. Chris

22 years, 9 months

Multitech/Acer Micro-Professor info WTD

by mhstein＠usa.net

Re AIM printers: I assume you're talking about the 20 col printer and not the -40; I've got a pile of these (not necessarily working, alas), but no markings on them other than Rockwell's. FWIW, the same printer was used by National Semi in at least one of their printing calcs, and I used to snap those up at junk shops for $5.00, a welcome discovery after having paid $150 ea for them from Rockwell & Dynatem. The 40 col model (very similar construction) was made in Japan, FWIW. Maybe there's still a helpful old-timer at Dynatem who could help you out; also, I assume you know that the AIM was disguised as a Siemens PC100 on the other side of the pond. mike --------Original Message-------------- From: "Philip Pemberton" <philpem(a)bigfoot.com> Subject: Multitech/Acer Micro-Professor info WTD <snip> Just out of interest, what sort of printer mech does the AIM-65 use? I'm not condoning the destruction of a perfectly good AIM-65 just to find this out, but I would like to know (in case anyone has a parts list for the AIM). Thanks again. - -- Phil. philpem(a)bigfoot.com http://www.philpem.btinternet.co.uk/

22 years, 9 months

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test-drb December 2001