The scanner module may be used in conjunction with the CRC module to perform a CRC
calculation over a range of program memory or Data EEPROM addresses. To set up the
scanner to work with the CRC, perform the following steps:
- 1.Set up the CRC module (See the
Configuring the CRC Module section) and enable the scanner module by
setting the EN bit in the SCANCON0 register.
- 2.Choose which memory region the
scanner module needs to operate on and set the MREG
bit appropriately.
- 3.If trigger is used for scanner
operation, set the TRIGEN
bit and select the trigger source using the SCANTRIG register. Select the trigger source using the SCANTRIG
register and then set the TRIGEN bit.
- 4.If Burst mode of operation is
desired, set the BURSTMD
bit.
- 5.Set the SCANLADR and SCANHADR registers with the beginning and ending
locations in memory that are to be scanned.
- 6.Select the priority level for the
scanner module. (Refer to the “System Arbitration” and the “Priority
Lock” sections for more details.)
Note: The default priority
levels of the system arbiter may need to be changed to ensure the
scanner operates as intended and that a memory access request is granted
when it occurs.
- 7.Both EN
and GO bits in the CRCCON0 register must be enabled to use the scanner. Setting the
SGO bit will start the scanner operation.