Optimum programming - Revision history

Jnc: +also 'minimum access coding'

2024-03-24T20:13:10Z

+also 'minimum access coding'

Jnc: Minor clarifications

2024-03-19T11:33:50Z

Minor clarifications

Jnc: Reasonably complete

2024-03-18T22:34:12Z

Reasonably complete

New page

'''Optimum programming''' (also called '''optimal coding''') was the name for a programming technique sometimes used on computers whose [[main memory]] was not [[random access]], but sequential (such as [[delay line]]- and [[drum]]-based memory).

In computers with such memory whose [[instruction]]s all include the [[address]] of the next instruction (i.e. they do not have a [[Program Counter]]), it was possible to scatter the instructions through the memory such that when any given instruction finishes its [[execute|execution]], the memory is just ready to provide the next instruction (which could/would be given by the 'next instruction' field in the prior instruction). This ensured that the computer was never wasting time waiting for the memory to provide the next instruction it needed.

Initially, the task of placing the instructions in memory at appropriate locations to allow this was left up to the programmer(s); eventually software tools (such as [[assembly language|assemblers]]) which did all the book-keeping necessary to automagically assign instructions to the appropriate addresses were written.

Among computers which used this technique were the [[Automatic Computing Engine|ACE]] and its descendants (including the [[Pilot ACE]] and the [[DEUCE]]), the [[Bendix G-15]], and the [[IBM 650]].

==External links==

* [http://www.bitsavers.org/pdf/ibm/650/32-7646-1_SOAPII.pdf SOAP II] - optimizing assembler for the IBM 650

[[Category: CPU Basics]]
[[Category: Software Basics]]

← Older revision		Revision as of 20:13, 24 March 2024
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−	'''Optimum programming''' (also called '''optimal coding''') was the name for a programming technique sometimes used on computers whose [[main memory]] was not [[random access]], but sequential (such as [[delay line]]- and [[drum]]-based memory).	+	'''Optimum programming''' (also called '''optimal coding''', and '''minimum access coding''') was the name for a programming technique sometimes used on computers whose [[main memory]] was not [[random access]], but sequential (such as [[delay line]]- and [[drum]]-based memory).

	In computers with such memory whose [[instruction]]s all include the [[address]] of the next instruction (i.e. they do not have a [[Program Counter]]), it was possible to scatter the instructions through the memory such that when any given instruction finishes its [[execute\|execution]], the memory is just ready to provide the next instruction (whose address could/would be given by the 'next instruction' field in the prior instruction). This ensured that the computer was never wasting time waiting for the memory to provide the next instruction it needed.		In computers with such memory whose [[instruction]]s all include the [[address]] of the next instruction (i.e. they do not have a [[Program Counter]]), it was possible to scatter the instructions through the memory such that when any given instruction finishes its [[execute\|execution]], the memory is just ready to provide the next instruction (whose address could/would be given by the 'next instruction' field in the prior instruction). This ensured that the computer was never wasting time waiting for the memory to provide the next instruction it needed.

@@ Line 1: / Line 1: @@
 '''Optimum programming''' (also called '''optimal coding''') was the name for a programming technique sometimes used on computers whose [[main memory]] was not [[random access]], but sequential (such as [[delay line]]- and [[drum]]-based memory).
-In computers with such memory whose [[instruction]]s all include the [[address]] of the next instruction (i.e. they do not have a [[Program Counter]]), it was possible to scatter the instructions through the memory such that when any given instruction finishes its [[execute|execution]], the memory is just ready to provide the next instruction (which could/would be given by the 'next instruction' field in the prior instruction). This ensured that the computer was never wasting time waiting for the memory to provide the next instruction it needed.
+In computers with such memory whose [[instruction]]s all include the [[address]] of the next instruction (i.e. they do not have a [[Program Counter]]), it was possible to scatter the instructions through the memory such that when any given instruction finishes its [[execute|execution]], the memory is just ready to provide the next instruction (whose address could/would be given by the 'next instruction' field in the prior instruction). This ensured that the computer was never wasting time waiting for the memory to provide the next instruction it needed.
 Initially, the task of placing the instructions in memory at appropriate locations to allow this was left up to the programmer(s); eventually software tools (such as [[assembly language|assemblers]]) which did all the book-keeping necessary to automagically assign instructions to the appropriate addresses were written.
@@ Line 9: / Line 9: @@
 ==External links==
-* [http://www.bitsavers.org/pdf/ibm/650/32-7646-1_SOAPII.pdf SOAP II] - optimizing assembler for the IBM 650
+* [http://www.bitsavers.org/pdf/ibm/650/32-7646-1_SOAPII.pdf SOAP II] - address-optimizing assembler for the IBM 650
 [[Category: CPU Basics]]
 [[Category: Software Basics]]