Interdata Systems (Perkin-Elmer)


Perkin-Elmer 1610 (Interdata 8-16)

I have had this system in storage for about 33 years now, so I thought I would pull it out and get it working. After replacing a capacitor on the memory board and cleaning contacts on the tape drive I was able to get it powered up. I had to figure out the pin connections and baud rate on the interface board. I used an old laptop as a serial terminal.
The Perkin-Elmer 1610 is a slightly redesigned Interdata 8-16 and was to be sold as a 16 bit version of the 32 bit 3220 systems. I don't know how many were sold, this one was an evaluation system bought by the company I worked for to test the memory boards they were designing and building. The system uses a microcoded bit-slice CPU based on the AM2901 chips.
I had attached an old Ampex tape drive, which seems to still work, however I don't have any software to load at this time. I seem to recall loading diagnostics and possibly OS/16, but the tape I had with the system doesn't seem to have anything on it (or is no longer readable). I have been looking for a copy of OS/16 on sites like Bitsavers, but no luck. If anyone has a copy (or any other Interdata 16 bit software) please let me know.

1610 CPU board







Boot loader ready to load tape image.




Card cage. CPU board on top, memory board, Loader interface board, and Mag Tape interface board.



System in relay rack. Ampex tape drive on top, PE 1610 rack, and power supply. The old core memory unit at the bottom is not connected.








Memory board is constructed with a wire embedding teknique.†† Traces were rolled onto the board with epoxy coating and connected at the feedthroughs.Traces can cross each other because wire is coated with enamal.††






I also have a core memory board for the 1610.



RAM memory.†† I have more of the piggy-back modules to increase the RAM size.




Interdata Model One

I was given two of these systems in 1979.††† They had been in storage for several years before I obtained them and I have had them in storage for the last 34 years.†† One is missing the core memory board but the other is complete enough to operate.†† I powered them up with a variable transformer slowly to check for any shorted capacitors or power supply issues but they came up just fine with all voltages looking good.Not bad for a nearly 50 year old system! They both have problems with possible stuck bits, however I can examine memory and it looks like itís trying to execute instructions when stepping through memory.†† I donít have a schematic but I do have a programmers user guide which has all the instruction set and a good block diagram of the CPU.†† Itís similar to other Interdata models (3 & 4) so hopefully I will be able to find more documentation to help me restore it to working order.

The Model 1 is mostly 7400 series TTL with some DTL chips mixed in.††† There is no LSI chips and all registers and ALU done with basic gates.†† The CPU consists of 4 ten inch boards (control 1, control 2, control 3, register).

There is no UART for the teletype interface.†† The serial to parallel conversion and timing is all done through software.†† It does have a current loop interface for the teletype that converts the serial line to TTL levels and sends / receives bits through the carry bit with a special instruction.†† There are several programming examples in userís guide.

I hope to restore the system enough to load simple programs to demonstrate the system in operation.


Model One front panel (the one below had the front panel removed showing the backplane).






Model One Core Memory board (2K).


Model One 10-inch chassis from the back, with Control 1, Control 2, Control 3, Register, Core boards.


Control 3


Control 2


Control 1


Control 3







Core Memory board (2K)


I/O card Ė Line Printer Interface(may be from a model 3 or 4)


Back side of the Interface board.Note the wire-wrap section used to customize the interface.