Struthers-Dunn PLC (ca 1977) any help?

onavi said:

hello
I have inherited a (USED) barber-colman hobbing machine
It was sent up here from a sister company.
The majority of the schematics are missing.
It has a Struthers-Dunn inc. PLC
Model 75415 Serial# 11191 S-D77 controller
and S-D 64 expander.(probably ca 1977)
I have the statement list for the plc program
and a list of inputs & outputs.
I cannot get the sequence of operation behond a certain point
and not having the ladder schematic I am unable (as yet)
to get to the bottom of this.
I have some familiarity with Omron PLC instruction set
but I am unfamiliar with the Stuthers-Dunn.
Could some one kindly give me an idea of the
meaning of the intructions?

HERE THEY ARE:
(the first column is the instruction
the second is the address)

CMR (NO ADDRESS GIVEN) FIRST INSTRUCTION
CEN (NO ADDRESS GIVEN) SECOND INSTRUCTION
LDA 024
ORC 024
STO 025
OR 001
AND 105
LDAC 057
MR 000
ANDC 105
CMR 000 (ADDRESS GIVEN IN THIS INSTANCE)

(AND SO ON FOR 924 STATEMENTS)

And as far as I can see there are no other instructions in
the whole program (which has aprox. 924 statements)

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