This book by Winkel and Prosser is one of the classic computer engineering textbooks of the 1980s.

The first edition (1980) was written at a time when microcomputers were still rare - and the university lab was more likely to have a PDP-8/E minicomputer running experimental equipment, rather than anything based on microprocessors.

The latter chapters describe the design and construction of a PDP-8 clone (workalike), using LS TTL, and semiconductor memory.

If you are curious about the inner workings of TTL based machines of that era, and some of the design decisions that went into creating them - then this might be a useful reference.

A link to the second edition (1987) is below.

http://bitsavers.informatik.uni-stuttga ... d_1987.pdf

Oh, thanks for sharing!

Yes, I had a quick browse and it looks excellent. I'll certainly use it to help with a problem I have with my CSCvon8 CPU, which I think is noise related.

I have that book in paper somewhere..
People have used that book to build an actual PDP-8.

The book focuses on Top Down Design - and makes use of Algorithmic State Machines.

The architecture and logic design of the PDP-8 is covered in sufficient detail in Chapter 7 - and proceeds to present the design of a machine they called the LD-20 which would run PDP-8 code.

Unfortunately the book does not have the detailed schematics of the LD-20 - as these were available in another publication cited in the book. If anyone has a link to these documents I would be interested in how the design was physically implemented on a pcb.

Reading through the design detail - the implementation of the PDP-8 appears to be somewhat complex - and if you look at the cpu board of an early 1970s PDP-8/A it contains about 115 ICs.

Some of these may have been necessary because of the drive requirements of magnetic core memory - but I think even the PDP-8 appears overly complex - compared to some of the TTL processors discussed on this forum.

Any insights appreciated.


Ken

Did you find this mega-thread on VCFed (which immediately links to other threads...)
http://www.vcfed.org/forum/showthread.p ... -8I-Part-2

Thanks Ed,

I have already fallen down a digital "rabbit hole" - and found the complete design documentation to the LD20's predecessor - the LD12 - a complete kit to build a PDP-8 functional clone in TTL, from 1974.

I've posted links to this resource under a new topic in the Hardware section

viewtopic.php?f=17&t=609

Cheers,


Ken