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IBM 360 Supplemental Control Panel

by billdeg
Total messages in this thread: 2
Updated: [ IBM 360 Supplemental Control Panel ] 05/29/2010
An unidentified 1800, dated 1969. Click Image for larger view.
detailed pictures This is an IBM 1800 supplemental control panel I picked up on Ebay a few weeks ago. The service tag is 1969. It's full of SLT chips. My theory is that it may have been used to monitor data transfers or to make sure one machine was cabled up correctly to another, I don't really know. There were computer-like devices that used the CPU of the mainframe computer to test and manipulate the mainframe's data as an add-on function for diagnostics and repair purposes. This type of device contributed to the evolution of stand-alone microcomputers, the Altair was not simply a simplified PDP 8. Add a microprocessor and RAM to a device like this an">... [ read more ]

Notes on Bitstreamer II for Altair

by billdeg
Total messages in this thread: 1
From Tom of the Altair Yahoo Group: The Bitstreamer II works in an Altair mainframe and provides three serial ports plus parallel ports. The Bitstreamer II works at 4MHz with 8251A IO chips. The Bitstreamer II works atb 6MHz with 9551 IO chips. The Bitstreamer II has software available for the MDM 7.12 modem program and Tarbell 1011D controller CP/M. The Bitstreamer II can exist in an Altair with minimum port address conflict. The Bitstreamer II works with the VG Z-80, PR-III, and ZCB. The Bitstreamer II works with the VG 2K 4.0C monitor and my 4.0x monitor. Source code is available for both Z80 monitors. ">... [ read more ]

Multimachine Games using 2 PET 2001s

by billdeg
Total messages in this thread: 3
Updated: [ Flash Attack for the PET ] 05/24/2010
Two Commodore PET 2001's linked in chat mode. Click image for larger view.
In honor of the PET Alive! event, I thought I'd take a crack at the experiments listed in the article Multimachine Games by Ken Wasserman and Tim Stryker from Byte December 1980, page 24. Their premise is that games are best played against another person, not the computer. They describe the principles for setting up a communications between computers for multiplayer gaming, and they give some examples. Note that the code in the article only works for the 2001 model, not the 4000 series. Not sure about the 3000 series, those were not sold in the US. At VCF 9 Larry Anderson had an">... [ read more ]

Chase lights program for IMSAI 8080

by billdeg
Total messages in this thread: 2
Updated: [ Better Solutions ] 05/16/2010
Here's a program you can toggle into your IMSAI 8080 that should display the "chase the lights" effect in your programmed output section. Text edit suggestions by Andy Meyer and Bill Dromgoole, program suggestion by Mike Loewen. First, turn on your IMSAI and toggle the STOP switch, them the RESET switch, then STOP again. Second, flip all of the data switches down and flip the Examine switch up. (This says "I want to work with address location 0000") Third, enter the following instructions into memory. (NOTE: DEPOS is a bi-directional momentary switch - it will not stay up or down. When you flip the switch up, you're telling the computer to deposit a value into the memory location you EXAMINE(d). When you flip it down, you're telling the computer to deposit a value into the NEXT memory location.) IMPORTANT! All ADDRESS - DATA switches should always be in the down ">... [ read more ]

Trenton Computer Festival 2010

by billdeg
Total messages in this thread: 1
Bob Applegate and son, and the MITS Altair 8800 on display
As with the past five years, MARCH had an exhibit booth in the clubs area of the Trenton Computer Festival. Club members picked up a few choice items from the flea market, and a few MARCH-ians had their own tables. Evan did his vintage computing for newbies talk on Saturday around 1PM, and then Bill and Evan hosted a lecture on the History of Computing in the Mid-Atlantic Region of the US. Download PDF format 3.9 Mb More Pictures Proceedings from TCF 2010: http://tcf-nj.org/proceedings/index.html">... [ read more ]

Dysan PAT-2+

by billdeg
Total messages in this thread: 1
New Project Dysan PAT-2+ Performance Alignment Tester and 8" 48TPI 360 RPM 2 Sided drive - disk 360/2A. More to come.">... [ read more ]

An S-100 Bus System Monitor Board

by monahan_z
Total messages in this thread: 1
For those that may be interested Andrew and I just finished a prototype of an S-100 bus "System Monitor Board". The board has the following features:- HEX LED display of all Data and Address lines. At all times the address of the master (or slave) CPU's program counter is displayed as a Hex LED display. If an 8 bit CPU is controlling the bus the current 8 bit instruction it is reading is displayed. If a 16 bit CPU is currently the master the 16 bit bidirectional data bus is displayed. Note because most 16 bit CPU's pipeline their instructions the data in and address bus may be slightly ahead of the actual instruction the CPU is executing. Hardware Breakpoint Switches. The board has a row of 20 small dip switches and circuitry such that if the CPU ever goes to a specified address it will stop. From there it can then be single stepped forward one CPU instruction at a time dis">... [ read more ]

Photos of CBM 8256068 MB

by billdeg
Total messages in this thread: 1
The CBM 128-80 high-profile B Series computer was never sold as "B700" in the USA, although a few low-profile B128-80's were sold as B500's. Hi-profile systems with a motherboard P/N 8256068 (without the -1 or -4) were made about the same time as the B500 was produced so unofficially you could call these systems "B700's". Anyway, I was asked to post some pictures of the motherboard, there is no reference to the earlier version elsewhere that I can find. Here you go: 8256068 pics NOTE: If I am wrong about this, kindly advise...this is info I got from an ex Commodore repair tech, I am going with his authority on the subject.">... [ read more ]

Announcement: CP/M Programming Workshop

by ragooman
Total messages in this thread: 2
Updated: [ Photos of CP/M Workshop 4-10-10 ] 04/11/2010
WORKSHOP: Installing CP/M on your S-100 computer signup begins Feb.1st See Checklist below announcement ------------------------------------------------------------------- NOTE: If you have other computers such as the Kaypro, Advantage, etc which already have CP/M running, you can use this too. They just need to be 100% working. As this is not a repair workshop. Basically, even though it would have CP/M already running on this, the hands-on training will show you all the technical details about how to configure and install CP/M on your current machine. Then you can apply this knowledge to any other machine that wouldn't have CP/M already. You would need to get prepared with all the technical manuals for your machine to extract the configuration info so you can edit and patch the CP/M source code to support your machine(that's what you will learn). We would help">... [ read more ]

Toshiba T1100 Plus System Disk

by billdeg
Total messages in this thread: 1
Toshiba T1100 Plus System Disk uploaded to Toshiba T1100 directory.">... [ read more ]

Cromemco System One

by billdeg
Total messages in this thread: 7
Updated: [ CDOSGEN was the answer ] 04/09/2010
I have just started working on this computer. I received it partially unassembled. I am unsure whether it worked or not. Fun. Cromemco System One Pics First I downloaded a copy of the System One user's guide, and using that document set the dip switches and cable up the computer. I also removed the Cromemco TU ART card card because the stock System One does not come with it and I wanted to start from stock first. I have to read the manual to determine how it interacts with the rest of the "stock cards" Here are pics of the cards that come with the System One. Cromemco 16 KZ memory card Cromemco PRI card Cromemco Z80 "ZPU" processor card ... [ read more ]

NEC 6001a Fonts

by billdeg
Total messages in this thread: 1
I received the following inquiry: "..I'm a user of Japanese NEC PC-6001 (not PC-6001A) Do you have NEC PC-6001A? If you have it, can you test this program and report as screenshot for me? This screenshot is VDG Font. .." RAM 16KB 5 SCREEN1,1,1:CLS 10 FORI=32TO255:PRINT CHR$(I);:NEXT 20 FORI=32TO255:POKE &HC000+I-32,0:NEXT RAM 32KB 5 SCREEN1,1,1:CLS 10 FORI=32TO255:PRINT CHR$(I);:NEXT 20 FORI=32TO255:POKE &H8000+I-32,0:NEXT ---------------- I have the 16K version, this it the program that I ran, here are the results: ----------------
When the program runs this is the first set of characters that appear on the screen, but you have to be quick, they only stay visible for a second.

BBC Interview about MITS Altair

by billdeg
Total messages in this thread: 1
I was interviewed on BBC last night on the subject of the Altair and it's historical importance. Here is essentially a transcript of the interview, but I assume they trimmed out things to fit whatever they were using it for. I do not have a copy of the audio, or know when it was broadcast. Q What's an Altair 8800 like? BD: The Altair was first sold in early 1975 and was extremely primitive for today's standards running at a minute fraction of the processor speed and memory. The computer itself was housed in a blue and grey metal box, about 50 centimeters deep by 18 centimeters tall (or 7 inches by 20 inches). The only way to interface with the Altair was through a series of toggle switches on the front which were used to enter machine language commands one at a time in octal or hexadecimal notation. There was no keyboard or video screen. In fact the only "display," i">... [ read more ]

Decwriter II

by billdeg
Total messages in this thread: 1

A Digital Equipment Corporation Decwriter II Model LA36 upgraded to 1200 baud.Pictures
This printer works, tested, OK.">... [ read more ]

Teletype Model ASR 33 with Phone Option

by billdeg
Total messages in this thread: 1

Teletype Model ASR 33 with Phone Option.Pictures
">... [ read more ]
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