HP-9830A & Mars Viking Mission

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An excerpt from Interface Age, Viking Uplink, vol. 2, issue 9, August 1977, pages 56 - 66

… This article describes the communication system between Viking I and the scientists. The programs published here are actual printouts of "conversations" with the lander during the evening of June 23, 1977. …
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INTRODUCTION
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   Three desktop computers are playing an integral part in this successful operation of the surface samplers and lander cameras. These computers are employed by the surface sampler and lander imaging teams in the generation and checking of all planned sequences which are to be sent to the landers. The process requires a great deal of precise bookkeeping and the equipment has to be available at any time without prior notice. Minicomputers were chosen for the task because of their stand-alone nature which in effect gives them a higher degree of reliability than larger systems which must be shared with other users and which would require a major effort to be brought back into operation in the event of a systems crash.
   The computers used are Hewlett Packard 9830A's, two of which have INFOTEK memory boards while the third has a Hewlett Packard memory. The INFOTEK cores were chosen because INFOTEK could offer 16K words of memory, whereas Hewlett Packard could only provide 8K at the time of purchase. Even 16K is somewhat inadequate and has strongly influenced the structure of the programs used. The relative slowness of the machines has also caused problems at times, but even so, the wisdom of choosing minicomputers for the job can hardly be denied. Their ease of operation and almost trouble-free history has more than made up for their lack of size and speed.

EQUIPMENT DESCRIPTION
The computers are Hewlett Packard Model 9830A's which program in Hewlett Packard BASIC. …
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THE PROGRAM
   The lander imaging team uses the program which is
flowcharted in Figure 1 and listed in Figure 2 (see page 78) …
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   The program actually consists of two programs … The programs are written in Hewlett Packard BASIC which is very similar to most other forms of BASIC or FORTRAN. …
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