82555 — Networking Silicon
The TOUT pin is controlled by different sources according to the active test instruction. The TOUT signal is activated by the falling edge of TCK. The TAP must be reset during
The TAP should be reset only with a hardware reset input pin and not with software reset. The TOUT control logic selects the TISR output in all tests, except
Table 6. Test Instruction Coding
Number | Code | Test Instruction | Select Input to TOUT |
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1 | 00000 | Idle | TISR D4out |
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2 | 00001 | Reserved | TISR D4out |
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3 | 00010 | ||
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4 | 00011 | NAND Test | TISR D4out |
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42 | Datasheet |