SPI and arrays on the 5LP

[Anonymous]

I'm doing a simple operation on the Cypress PSOC 5LP 59. It uses SPI to communicate with a Raspberry Pi which sends a bunch of letters, and the PSOC 5LP blinks a light after it receives a certain letter. The PSOC stores the entire array of letters.

       

This does not work for some reason. It works if I use a buffer of 100 letters, and the A is the 95th letter or something. It works up to 400 letters or so (though it will be slightly sporadic sometimes.) But after that point, it won't work. For a buffer size of 1000, with the first A being at the 800th letter, the LED won't turn on. 

       

The SAME code, works with the 4200 with a buffer of 2000. So why does it not work with the 5LP? Its max array size should definitely not be 400 or so. 

[Anonymous]

As far as buffer size goes, the compiler will give you an error if your buffer is too large to fit in SRAM.

   

This line might be causing you problems:

   

            while(1u != SPIS_GetRxBufferSize()) // wait till byte is recived

   

If you're running the SPI bus at high speeds, RxBufferSize could skip from zero to 2 before the polling loop has a chance to check that register. It would be safer to use "while (size() == 0)".

[Bob_Marlowe]

Can you please post your complete project, so that we all can have a look at all of your settings. To do so, use
Creator->File->Create Workspace Bundle (minimal)
and attach the resulting file.

   

As I see, your variable "i" is not incremented.

   

Bob