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Hello from Southern Mississippi:
Subroutine Calls are initiated
with a simple JST (Jump and Store Return) instruction. This is the
mechanism:
LDA Money To pass an
argument
JST DO
CMP Lost
DO PZE
Initially Zero
ADD Anything
My design executes the LDA and
JST in parallel. The JST stores the incremented PC in DO, and executes the
instruction DO+1.
Upon completion of SUBR Called (DO), an
Indirect Jump is executed, JMPN.
JMPN DO Return to JST +
1
Priority Interrupts are handled
in the same manner; as an Interrupt is nothing more that a JST
I don't have to consider what
Register does what, as I don't have any. My registers are in Operand
(Local Memory) . I potentially have 256K of Registers.
Have a good day
Richard Hartney
Erin Greene & Assiciates
Business Information Management
Systems
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