I am unsuccessfully trying to write data to the SPI EEPROM 25C040.
I have a 1 MHz SPI clock,
I CAN request and receive the status from the device.
I CAN set and clear the Write enable latch,
(So I'm sure the SPI drivers are operating...)
But I can not write data to the device....

(Checking the status show NO Write In Progress.)
I am SURE I have done all the required conditions,
and have an HP logic analyzer to verify the SPI transactions.
(Byte flow, and Chip select.)

Questions/Observations...

After much flailing I consulted the example code for the device.
The code ADDS a little "Oh! By the way..."
They add a DELAY loop between the request for status,
and shifting out the status data.

WHERE is this delay specification printed?
(The spec. sheeet DS21204C has no such delay.)

Are there other delays not mentioned in the spec that might be the reason
I can not write to the device?
(I know about the 5 ms write delay.)

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  |  __O    Thomas C. Sefranek  tcs@cmcorp.com
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