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"check whether the number of byte transmitted is equal to the number of bytes received"
This is an SPI thing, your LCD will send back data although they might be meaningless. For every bit (byte) you send as master a bit (byte) is received from the slave. So you may check whether the number of bytes received is equal to the number of bytes sent. That would indicate a complete transfer, including delay times in the sender / receiver part. Some of the serial components use an internal (!!) interrupt to make sure that the data is fetched from FIFO and stored in memory thus avoiding overflows. This could interfere with your own interrupt handlers.
There is an extension to the SPI internal interrupt named "Macro Callback", search for this string in the datasheet for explanation. Some general information is in Creator Help.
Opposed to competitor's chips, PSoCs contain real hardware. so the component's datasheet are made in the style of electronic datasheets. When used to them, they are easy to read and understand.
Hi Bob, thanks for your replay. I am not sure whether the SPI does require both MOSI and MISO exist together. However in my LCD module, which use a popular LCD driver IC, there is no MISO pin. Also in the Cypress configuration, we can set the SPI component to remove the MISO pin.....
I can leave the MISO pin on the SPI component there, however is it good if this pin is useless? Especially in the case that we have used up all IO pins.
Try the bi-directional mode for your SPIM, see picture in datasheet. There is an internal loopback so you can still see when transmission is done.