Interface Input/Output Test (IOTEST)
Use IOTEST to test the input and output data busses of the signal processor interface.
When issued, the command causes 16 words to be read from the host controller, after which the same 16 words are printed.
Typically, the controller supplies a "barber pole" input sequence consisting, for example, of successive powers of two. If all of the output words are correct, one may conclude that there are no malfunctioning bits in the interface hardware
15 14 13 12 11 10 9 8 7 6 5 4 3 2 1 0
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| | | | | | | | | | | | | | | | |
| | 0 0 0 1 1 | Command
|-------------------------------------------|-------------------| 15 14 13 12 11 10 9 8 7 6 5 4 3 2 1 0
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| | | | | | | | | | | | | | | | |
| Arbitrary Data Word #1 Supplied by Host Controller | Input 1
|---------------------------------------------------------------| 15 14 13 12 11 10 9 8 7 6 5 4 3 2 1 0
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| | | | | | | | | | | | | | | | |
| Arbitrary Data Word #16 Supplied by Host Controller | Input 16
|---------------------------------------------------------------| | The IOTEST command can also process and echo up to 128 additional XARGS data words. See Pass auxiliary arguments to opcodes (XARGS). |
15 14 13 12 11 10 9 8 7 6 5 4 3 2 1 0
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| | | | | | | | | | | | | | | | |
| Copy of Data Word #1 Supplied by Host Controller | Output 1
|---------------------------------------------------------------| 15 14 13 12 11 10 9 8 7 6 5 4 3 2 1 0
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| | | | | | | | | | | | | | | | |
| Copy of Data Word #16 Supplied by Host Controller | Output 16
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