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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 ]

Misc computer photos

by billdeg
Total messages in this thread: 1

Recently I have been given a number of new sets of computer books and software related to varied 80's operating systems including OS/2, MS DOS, and CP/M, Novell, Banyan, MAC, Osborne and Kaypro; hardware docs; miscellaneous harware including disk drives (SSQD/DSDD), printers, modems, and SCSI hard disk drives. Pictures
">... [ read more ]

Wangwriter Terminal

by billdeg
Total messages in this thread: 1

A Wangwriter Terminal. I no longer have the computer system. Pictures... [ read more ]

Atari 800 XL

by billdeg
Total messages in this thread: 1

A boxed Atari 800XL Computer system with peripherals. Pictures
">... [ read more ]

Dynabyte DB8/1

by billdeg
Total messages in this thread: 1
This is a restoration program for MARCH for a Dynabyte S-100 system, not to be confused with the Dynabook prototype laptop from Xerox.
The Dynabyte DB8/1 was an early 80's S-100 system that employed the IEEE 696 standard. Click image for larger view.
So far the system has been partially disassembled. The controller cards have been visually inspected (1800002-4A CPU, 64K dynamic RAM Dual Drive Controller). The card connectors have been cleaned, the entire chassis has been vacuumed clear of dust. <">... [ read more ]

Kaypro II pad PLA?

by billdeg
Total messages in this thread: 1
Kaypro II Portable.
The computer powers on, but the drive does not spin, nor does the system respond to a warmboot. The picture you see here is actually a still shot of the screen flashing characters in a rotating pattern of gibberish. I *think* the PLA is bad, 81-149C. Once when pressing down the PLA the system almost completed a boot cycle. I tried a known-working Z80, but no change in outcome.
I have had this system for years, but I never took time to see why it does not boot. Finally this weekend I took it apart to find that the inside condition is pretty bad/dirty. Note the rusty port connectors. ">... [ read more ]

Zenith minisPORT laptop

by billdeg
Total messages in this thread: 1
The Zenith minisPORT laptop computer c. 1990. This is the 2MB ZL-2 model. The ZL-1 came with 1MB. Click thumbnail for larger image.
The Zenith minisPORT is an otherwise standard 80c86 LCD display laptop which is best known because of its 2 inch disk drive.
The Fuji 2 inch LT-1 diskette had a formatted capacity of approximately chkdsk displays 812K. Zenith sold an optional 720K external 3.5 drive. The internal 2 inch drive is not only smaller but it has more capacity (800+ Kb) than the 3.5 drive!
... [ read more ]
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