PIC18F87K22 Datasheet, PDF (426/548 Pages) Microchip Technology – 64/80-Pin, High-Performance, 1-Mbit Enhanced Flash Microcontrollers with 12-Bit A/D and nanoWatt XLP Technology

PIC18F87K22 FAMILY
FIGURE 28-8:
EXTERNAL BLOCK TABLE READ (EBTRx) DISALLOWED
Register Values
TBLPTR = 0008FFh
Program Memory
000000h
0007FFh
000800h
Configuration Bit Settings
WRTB, EBTRB = 11
WRT0, EBTR0 = 10
PC = 007FFEh
TBLRD*
003FFFh
004000h
007FFFh
008000h
00BFFFh
00C000h
WRT1, EBTR1 = 11
WRT2, EBTR2 = 11
WRT3, EBTR3 = 11
00FFFFh
Results: All table reads from external blocks to Blockn are disabled whenever EBTRx = 0.
The TABLAT register returns a value of ‘0’.
FIGURE 28-9:
EXTERNAL BLOCK TABLE READ (EBTRx) ALLOWED
Register Values
Program Memory
000000h
0007FFh
000800h
Configuration Bit Settings
WRTB, EBTRB = 11
TBLPTR = 0008FFh
WRT0, EBTR0 = 10
PC = 003FFEh
TBLRD*
003FFFh
004000h
007FFFh
008000h
00BFFFh
00C000h
00FFFFh
WRT1, EBTR1 = 11
WRT2, EBTR2 = 11
WRT3, EBTR3 = 11
Results: Table reads permitted within Blockn, even when EBTRBx = 0.
The TABLAT register returns the value of the data at the location, TBLPTR.
DS39960B-page 426
Preliminary
 2010 Microchip Technology Inc.