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What items to checked if initial operation is not working correctly?

Latest Updated:03/23/2009


The board has been made, but initial operation is not working correctly. What items should be checked?


Please check the following.

1) Is each power supply supplied correctly?

2) Is a correct potential applied?

3) Are clocks input to SH-4?

4) Is RESET negated(High)?

5) Is MRST negated(High)?

6) When using H-UDI: Is TRST driven low for a period overlapping RESET at power-on?

When not using H-UDI: Is TRST fixed to the ground or connected to the same signal line as RESET?

7) Are MODE<8:0> or MODE<10:0> fixed to each setting level ('High" or 'low')?

8) Does CKIO output expected frequency?

9) Is access to Area0 performed after releasing a power-on reset

(SH-4 accesses to h'a000 0000 when a power-on reset is released).

10) Is RDY asserted (low)? (RDY at high means wait.)

11) CA pin is reserved pin in the SH7750, but please pull up CA pin at +3.3V.

(CA pin must be pulled up externally when hardware standby is not used).

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