PIC18C658 MICROCHIP [Microchip Technology], PIC18C658 Datasheet - Page 65

• Manufacturer Part Number: PIC18C658
• Description: High-Performance Microcontrollers with CAN Module
• Manufacturer: MICROCHIP [Microchip Technology]

5.0
All PICmicro
program memory space and the data memory space.
Table Reads and Table Writes have been provided to
move data between these two memory spaces through
an 8-bit register (TABLAT).
The operations that allow the processor to move data
between the data and program memory spaces are:
• Table Read (TBLRD)
• Table Write (TBLWT)
FIGURE 5-1:
FIGURE 5-2:
 2000 Microchip Technology Inc.
Note 1:
Instruction: TBLRD*
Instruction: TBLWT*
Note 1:
TABLE READS/TABLE WRITES
®
Table Pointer points to a byte in program memory.
TBLPTRU
TBLPTRU
Table Pointer points to a byte in program memory.
devices have two memory spaces: the
TABLE READ OPERATION
TABLE WRITE OPERATION
TABLE POINTER
TABLE POINTER
TBLPTRH
TBLPTRH
Program Memory
(TBLPTR)
(1)
(1)
Program Memory
(TBLPTR)
TBLPTRL
TBLPTRL
Advanced Information
PROGRAM MEMORY
PROGRAM MEMORY
Table Read operations retrieve data from program
memory and place it into the data memory space.
Figure 5-1 shows the operation of a Table Read with
program and data memory.
Table Write operations store data from the data mem-
ory space into program memory. Figure 5-2 shows the
operation of a Table Write with program and data
memory.
Table operations work with byte entities. A table block
containing data is not required to be word aligned, so a
table block can start and end at any byte address. If a
table write is being used to write an executable pro-
gram to program memory, program instructions will
need to be word aligned.
TABLE LATCH (8-bit)
TABLE LATCH (8-bit)
PIC18CXX8
TABLAT
TABLAT
DS30475A-page 65