there was a machine

THE SEAC

by IDA RHODES

Say itís weary, say itís slow,
Say that luxury ignored it,
Say
itís growing old, but know
We all adored it.


SEAC was born on the wrong side of the tracks with only 11 commands and 512 storage registers, but in the hearts of its grateful users this prodigy has left a glowing spot that none of its opulent, sophisticated successors will ever dislodge. In fact, I often shed a tear for the nouveau riche programmer: a programmer who is unable to communicate with his machine in its own natural language, but must instead transmit his intent in the alien speech of the Court; a programmer who is denied the thrill of personally wielding a tremendously powerful, yet utterly compliant, tool; a programmer who is bereft of the mentally invigorating need ever to explore new means for squeezing a maximum of information into a minimum of storage space; a programmer who is deprived of the privilege to effect ameliorating changes in the structure of his machine.
†† Ere future generations venture to sneer at SEACís operational speed of one millisecond for addition and three for multiplication, let them ponder over those sweet uses of adversity from which the pioneers in electronic computation derived such huge benefits. SEACís devotees could rightfully assert that it was the first device in this country to function with an automatically sequenced, internally stored program, but that claim would be based on a technicality. Much of its success must be credited to the advances made by previously conceived instruments, whose gestation periods were necessarily prolonged because of their higher degree of sophistication and more ample physical endowment. But we do claim with gusto that its features have been a source of ease and comfort to the tyro programmer and coder.
†† Take for example its four-address system, which in the early stages was SEACís only mode of control. What could be a more natural bent for the coder than to direct the machine to perform a basic process on a pair of operands located at the first two addresses, to store the result at the third, and to look for the next command at the fourth? If it were found necessary to omit, or to alter the sequence of, a set of instructions, a readily effected change in the fourth address of a command or two would correct the routine at once. Additional aid was granted by the fact that SEAC needed only one command for reading into the storage, and again only one command to write out.
†† Humble SEACís time was so inexpensive that the coder could frequently allow himself the luxury of code-checking and correcting his routine all in one run. Since each command bore a break-point bit, key instructions were usually coded with it. If a routine ran into trouble, a flick of a console switch caused the result of every such instruction to be printed out. In dire distress, the coder could, by a switch setting, automatically monitor the results of every consecutive operation. With what dignified silence has our noble SEAC borne the base canard that its mercury tanks were misbehaving - a pretense so often voiced by the human bungler as he resorted to that all-too-handy switch!
SEACís users enjoyed a priceless boon in the constant presence of its creators. Not only did these magicians watch unceasingly over their brainchild, but graciously permitted us to offer suggestions, while they continuously introduced improvements that amazed and delighted us. The SEAC of today bears little resemblance to the immature fledgling of 1950; and as it grew and developed, so did the skill and confidence of the pioneer coder. That Spartan individual was never compelled to swallow the predigested pap prepared by the Higher Caste for the benefit of the Untouchables. He knew the precise location and function of every bit in his routine, and he learned to manipulate the computer with the same care and reverence that a dedicated musician accords the instrument of his choice.
†† Now that SEAC has passed into glorious history, let a tender tribute be recorded for posterity to this superbly diligent, faithful, and efficient servant that so frequently doubled as a serenely patient and exceedingly effective trainer.

 

The SEAC
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From Datamation (a defunct computer magazine), September 1964

 

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