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Altera_Forum
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20 years ago

Clever UARTs (Interrupt Driven)

Hello all, By this time I know that everybody is tired of this topic, but I can't seem to find a clear answer anywhere. Firstly, I am not using a RTOS but am wanting to use the RX & TX...
Altera_Forum's avatar
Altera_Forum
Icon for Honored Contributor rankHonored Contributor
20 years ago

Hi tyrone,

My ring buffer sizes are powers of 2, usually 512 bytes. I have two variables that tell me where the 'in' and 'out' positions are. When characters are inserted or removed these indexes are incremented, I then &= them with a mask that keeps them in range and takes care of the wrap around. For a 512 byte buffer the mask is 0x1ff. Quick and simple.

Banx.