Products > Test Equipment
Some old school instruments showing how it's done (HP 3325A and Fluke 8506a)
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joeqsmith:
More the beginning of my own personal downfall.  8080s, assembler....  obviously a mental problem.   :-DD   

I tried getting some of the old tools to run.   CMP86 will run under a DOSbox.  CMP86 will run Jim Lopushinsky's Z80.CMD.      The Z80.CMD will all run the old Digital Research simulator/debuggers to some level.  It will also run the old Microsoft  assembler, to some degree.   I just haven't been able to actually assemble a program and link it.    Attempting to just get something very basic to work.  2 lines of code sort of thing.  Baby steps.     

It really is starting to look like we need some better tools for 2021.
SilverSolder:

Better tools for 8080 will probably be a DIY project...
joeqsmith:
Some success with the Microsoft tool set.   I was able to assemble and link some fairly large 8080 syntax programs with it.
joeqsmith:
I'm still sorting out the syntax for the old tools and reading up on the old 8080.   These tools and their documentation are all available for free on-line if anyone is interested attempting to use them.  Seems only fitting to use these old tools to hack the old meter.    :-DD

Looking at the example code from:
https://en.wikipedia.org/wiki/Intel_8080#Example_code

I changed the origin to 0 and removed the return just to give me a simple program to test with.   Attached is the listing from the Microsoft tools.   

Again, you would need to setup a DOSBox, download Jim's tool set (from 1985  :-DD) and download the Microsoft macro assembler and linker.   I am just running it from all from the command prompt using a batch file to automate the process.    I have not yet worked out the Digital Research tools.   

If I had another junk meter, I would replace that U18 prom with a GAL with a custom memory map that would place all of the code in U24.   I may still do this with a small plug in board.  This may make things easier once I actually start to look at and modify the original code.   


       MACRO-80 3.44   09-Dec-81       PAGE    1


                                ; memcpy --
                                ; Copy a block of memory from one location to another.
                                ;
                                ; Entry registers
                                ;       BC - Number of bytes to copy
                                ;       DEAddress of source data block
                                ;       HL - Address of target data block
                                ;
                                ; Return registers
                                ;       BC - Zero

                                            org     000h        ;Origin at 0000h
  0000'   78                                mov     a,b         ;Copy register B to register A
  0001'   B1                                ora     c           ;Bitwise OR of A and C into register A
  0002'   C8                                rz                  ;Return if the zero-flag is set high.
  0003'   1A                    loop:       ldax    d           ;Load A from the address pointed by DE
  0004'   77                                mov     m,a         ;Store A into the address pointed by HL
  0005'   13                                inx     d           ;Increment DE
  0006'   23                                inx     h           ;Increment HL
  0007'   0B                                dcx     b           ;Decrement BC   (does not affect Flags)
  0008'   78                                mov     a,b         ;Copy B to A    (so as to compare BC with zero)
  0009'   B1                                ora     c           ;A = A | C      (set zero)
  000A'   C2 0003'                          jnz     loop        ;Jump to 'loop:' if the zero-flag is not set.

                                        end
       MACRO-80 3.44   09-Dec-81       PAGE    S


Macros:

Symbols:
0003'   LOOP



No Fatal error(s)


s)
  0008'   78



SilverSolder:

LOL seems you are really getting into some serious digital archaeology there, @joeqsmith!  :D
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