There were many manuals for the IBM 5100-series. For the IBM 5110, there are three main commonly available manuals:

MIM = Maintenance Information Manual
MAP = Maintenance Analysis Procedures
GIP = General Information and Physical Planning Manual

Then additional manuals for BASIC and APL. I do have hard copies of the following:

IBM Introduction to Programming the IBM 5110 in BASIC (230 pages) (SR30 0310 0)
IBM 5110 BASIC Introduction (160 pages) (SA21 9306 0)
IBM 5110 BASIC Reference Manual (260 pages) (SA21 9308 2)
IBM 5110 BASIC User’s Guide (196 pages) (SA21 9307 2)

I also have the SLM (System Logic Manual) diagrams archived >>here<<

“The IBM 5100 Portable Computer” by Harry Katzan Jr, 1978

  • RND is the random number generator in BASIC, while APL uses “? n”
  • This book does not reference the diagnostic capability of the 5100 (i.e. it doesn’t describe machine language operation at all)

HERE is the maintenance manual that reads much like a detailed mechanics service manual for a car (like the HELMS manuals for major manufacturers like Honda) or an appliance like an air conditioning or refrigerator (that include details about sub-assemblies and pin-outs).

Within the MIM page 4-65, I came across the following interesting information about the use of the L32 and R32 switch combined with the SHOW REGISTERS switch: there are different sets of registers for each interrupt level.

Page 2-12 of the MIM has the following layout of what is essentially the motherboard of the system, simply called the “A1 board.”

Here is an overlay of the expansion components that I have:

Side by side comparison of the 5100 “CPU” and the 5110 “CPU.” They weren’t yet called CPUs, because the overall processing was really distributed across multiple boards. But the core “ALU” that would process PALM opcodes, and the corresponding clock rate, is located on these boards. The majority of part numbers is identical, with very few revisions between the two. But the mystery remains on how similar these were to the original 1973 SCAMP.

Leave a Reply

%d bloggers like this: