Dependencies; I/O Pins; Clocks; Other Registers - Rabbit 6000 User Manual

34.2 Dependencies

34.2.1 I/O Pins

There are no I/O pins associated with the Error Check and Correction peripheral.

34.2.2 Clocks

There are no clocks associated with the Error Check and Correction peripheral.

34.2.3 Other Registers

There are no other registers associated with the Error Check and Correction peripheral.

34.3 Operation

Before starting an operation, clear the internal counter by writing a 0 and then a 1 to bit 7 of ECCR. The
internal counter will not be cleared until this is done.

34.3.1 ECC

The following steps must be taken to perform Error Check and Correction calculations.
1. Enable the ECC peripheral and select the Error Check and Correction peripheral by writing to
ECCR. Select the initial value and read data direction if desired.
2. If desired, the initial state of the line parity bits can be set by writing to ECWxR, and the column
parity bits by writing to ECPR or ECPSR.
3. Start writing data to ECDxR.
4. When all data have been written for that block, read the line parity bit values from ECDxR for nor-
mal bit order, or ECWxR for reverse bit order. Read the column parity bit values from ECPR or
ECPSR.

34.3.2 CRC

The following steps must be taken to perform a CRC calculation.
1. Enable the Error Check and Correction peripheral and select the desired CRC operation by writing
to ECCR. Select the initial value and read data direction if desired.
2. If desired, the initial state of the CRC counter can be set by writing to ECWxR.
3. Start writing data to ECDxR.
4. When all data have been written for that block, read the CRC counter from ECDxR for normal bit
order, or ECWxR for reverse bit order.
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