Update 8/1/17

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Over the last week or so I have been busy with the other half of my UROP, the benchmarking. I will be benchmarking the PDP-12 and comparing its results to other machines. So far for test machines besides the PDP-12 I have a Commodore 64, a 286 PC, and a 486 PC.

For a while I was trying to rewrite Dhrystone to run in Fortran IV. After spending a few days on it I realized that doing so would likely alter how Dhrystone runs.

Dhrystone was written in Ada originally, and then ported to C and Pascal. All three of these languages support pointers and structs/records. Fortran IV does not. Not having pointers makes translating the code very difficult. There is Pascal for the PDP, but it requires 28k of core. We have 8k.

Whetstone seems to be a better fit. It was originally written in ALGOL 60, and there is a Fortran version available (Fortran 90, but I could rewrite it to IV). There is an ALGOL compiler for the PDP-8 (DECUS 8-213 4k ALGOL) called ALGOL 8. It is a subset of ALGOL 60. I have been having difficulties getting the compiler to run and compile simple test programs. At this point I am thinking I might stick with Fortran as I can run that on the other machines, minus the C64.

The C64 is built on a 6502 microprocessor and does not have a Fortran compiler that will run on a 6502 (as far as I have seen). There is a Fortran compiler that was written for the C64, but it requires the Z80 expansion cartridge. It would compile it for the Z80 microprocessor.

For the 286 and 486 I will look into the Microsoft Fortran Compiler or the IBM Fortran Compiler.


I did finish running the "straight 8" diagnostics again after our -30V mishap and everything checks out fine.


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