PIC18FXX20
DS39583C-page 34 2010 Microchip Technology Inc.
PIC18F6720
None SUM(0000:01FF)+SUM(0200:3FFF)+SUM(4000:7FFF)+
SUM(8000:BFFF)+SUM(C000:FFFF)+SUM(10000:13FFF)+
SUM(14000:17FFF)+SUM(18000:1BFFF)+SUM(1C000:1FFFF)+
(CFGW1L & 0000)+(CFGW1H & 0027)+(CFGW2L & 000F)+
(CFGW2H & 000F)+(CFGW3L & 0000)+(CFGW3H & 0001)+
(CFGW4L & 0085)+(CFGW4H & 0000)+(CFGW5L & 00FF)+
(CFGW5H & 00C0)+(CFGW6L & 00FF)+(CFGW6H & 00E0)+
(CFGW7L & 00FF)+(CFGW7H & 0040)
05A8 04FE
Boot
Block
SUM(0200:3FFF)+SUM(4000:7FFF)+SUM(8000:BFFF)+
SUM(C000:FFFF)+SUM(10000:13FFF)+SUM(14000:17FFF)+
SUM(18000:1BFFF)+SUM(1C000:1FFFF)+(CFGW1L & 0000)+
(CFGW1H & 0027)+(CFGW2L & 000F)+(CFGW2H & 000F)+
(CFGW3L & 0000)+(CFGW3H & 0001)+(CFGW4L & 0085)+
(CFGW4H & 0000)+(CFGW5L & 00FF)+(CFGW5H & 00C0)+
(CFGW6L & 00FF)+(CFGW6H & 00E0)+(CFGW7L & 00FF)+
(CFGW7H & 0040)+SUM(IDs)
077F 0734
Boot/
Block1/
Block2
SUM(8000:BFFF)+SUM(C000:FFFF)+SUM(10000:13FFF)+
SUM(14000:17FFF)+SUM(18000:1BFFF)+SUM(1C000:1FFFF)+
(CFGW1L & 0000)+(CFGW1H & 0027)+(CFGW2L & 000F)+
(CFGW2H & 000F)+(CFGW3L & 0000)+(CFGW3H & 0001)+
(CFGW4L & 0085)+(CFGW4H & 0000)+(CFGW5L & 00FF)+
(CFGW5H & 00C0)+(CFGW6L & 00FF)+(CFGW6H & 00E0)+
(CFGW7L & 00FF)+(CFGW7H & 0040)+SUM(IDs)
857C 8531
All (CFGW1L & 0000)+(CFGW1H & 0027)+(CFGW2L & 000F)+
(CFGW2H & 000F)+(CFGW3L & 0000)+(CFGW3H & 0001)+
(CFGW4L & 0085)+(CFGW4H & 0000)+(CFGW5L & 00FF)+
(CFGW5H & 00C0)+(CFGW6L & 00FF)+(CFGW6H & 00E0)+
(CFGW7L & 00FF)+(CFGW7H & 0040)+SUM(IDs)
480 048A
TABLE 5-4: CHECKSUM COMPUTATION (CONTINUED)
Device
Code
Protect
Checksum
Blank
Value
0xAA at 0
and Max
Address
Legend: Item
Description
CFGW = Configuration Word
SUM[a:b] = Sum of locations, a to b inclusive
SUM_ID = Byte-wise sum of lower four bits of all customer ID locations
+ = Addition
& = Bit-wise AND
