PDP-8/E
Introduction
The PDP-8/E was introduced in 1970 and had an 8 year run before sales ended in 1978 as interest shifted to the PDP-8/A. It cost $6,500 US. The CPU consisted of five quad boards (M8300 Major Registers, M8310 Register Control, M8320 Bus Loads, M8330 Timing Generator, M8560 Teletype Control) and operated at 385KHz. Memory cycle time was 1.2 micro seconds for the MM8-E 4K core memory (H220) which required 2 additional boards (G104, G227) for driver logic. An 8K core option was also available.
The front panel console was based on flip switches and lights. It featured a standard OMNIBUS backplane with 20 slots with no fixed module assignments although some modules were connected by jumpers and had to be placed sequentially.
The PDP-8/E was my first had hands-on computer experience in the mid 1970s. The computer was at Dawson College's Richelieu Campus in downtown Montreal. It had a Teletype, 4K words of memory and a high speed paper tape reader/punch. Natively it ran BASIC from memory, no loading was needed as the interpreter was already in core memory. A locked room housed this minimal system. I had the privilege having the key to the room after showing interest for doing some BASIC programming to my teacher. Not many people used this system so he was happy that someone had a use for it. I spent my Christmas break going into the college every day and locking myself up in the room with the PDP-8. I typed up an interactive computer game, similar to the interactive Star Trek computer game of those days. When loaded, the binary loader overwrote the BASIC interpreter. It turned out the game was larger than the 4K of memory. It was game over! A DEC technician had to be called to restore the system. My access privileges were suspended, but only temporarily.
PDP-8/E Console
Source: Wikipedia
PDP-8/E Options Summary
| Option | Description |
|---|---|
| KA8-E | Positive I/O Bus Interface. Allows use of older PDP-8 devices. |
| KM8-E | Memory Extension and Time-Share Option, which provided bank switching needed to support more than 4KW of memory, and allowed the computer to operate in either Executive Mode or User Mode. |
| FPP8/A | A floating point option was available on two cards; M8410 floating point processor control, M8411 data path card. |
| MP8-E | Memory Parity. |
| KD8-E | Data Break Interface. |
| KE8-E | Extended Arithmetic Element (two quad boards) which supported hardware integer multiplication and division, one-bit double-word shifts, and normalization. |
| FPP12-P/AP | Floating Point Processor (24+12 bits). |
| FPP12-AE | Double Precision option (FPP12-AP only, 60+12 bits). |
PDP-8/E Documents
PDP-8/E Chassis
Source: https://www.hb9aik.ch/computer/8E_front.jpg
Sources:- Adapted from: https://en.wikipedia.org/wiki/PDP-8