PIC24HJXXXGPX06A Datasheet, PDF (61/294 Pages) Microchip Technology – High-Performance, 16-Bit Microcontrollers

PIC24HJXXXGPX06A/X08A/X10A
5.0 FLASH PROGRAM MEMORY
Note:
This data sheet summarizes the features
of the PIC24HJXXXGPX06A/X08A/X10A
family of devices. However, it is not
intended to be a comprehensive reference
source. To complement the information in
this data sheet, refer to the “PIC24H
Family Reference Manual”, Section 5.
“Flash Programming” (DS70228), which
is available from the Microchip website
(www.microchip.com).
The PIC24HJXXXGPX06A/X08A/X10A devices con-
tain internal Flash program memory for storing and
executing application code. The memory is readable,
writable and erasable during normal operation over the
entire VDD range.
Flash memory can be programmed in two ways:
1. In-Circuit Serial Programming™ (ICSP™)
programming capability
2. Run-Time Self-Programming (RTSP)
ICSP programming capability allows a
PIC24HJXXXGPX06A/X08A/X10A device to be seri-
ally programmed while in the end application circuit.
This is simply done with two lines for programming
clock and programming data (one of the alternate pro-
gramming pin pairs: PGECx/PGEDx, and three other
lines for power (VDD), ground (VSS) and Master Clear
(MCLR). This allows customers to manufacture boards
with unprogrammed devices and then program the dig-
ital signal controller just before shipping the product.
This also allows the most recent firmware or a custom
firmware to be programmed.
RTSP is accomplished using TBLRD (table read) and
TBLWT (table write) instructions. With RTSP, the user
can write program memory data either in blocks or
‘rows’ of 64 instructions (192 bytes) at a time, or single
instructions and erase program memory in blocks or
‘pages’ of 512 instructions (1536 bytes) at a time.
5.1 Table Instructions and Flash
Programming
Regardless of the method used, all programming of
Flash memory is done with the table read and table
write instructions. These allow direct read and write
access to the program memory space from the data
memory while the device is in normal operating mode.
The 24-bit target address in the program memory is
formed using bits<7:0> of the TBLPAG register and the
Effective Address (EA) from a W register specified in
the table instruction, as shown in Figure 5-1.
The TBLRDL and the TBLWTL instructions are used to
read or write to bits<15:0> of program memory.
TBLRDL and TBLWTL can access program memory in
both Word and Byte modes.
The TBLRDH and TBLWTH instructions are used to read
or write to bits<23:16> of program memory. TBLRDH
and TBLWTH can also access program memory in Word
or Byte mode.
FIGURE 5-1:
ADDRESSING FOR TABLE REGISTERS
24 bits
Using
Program Counter
0
Program Counter
0
Using
Table Instruction
1/0 TBLPAG Reg
8 bits
Working Reg EA
16 bits
User/Configuration
Space Select
24-bit EA
Byte
Select
© 2009 Microchip Technology Inc.
Preliminary
DS70592A-page 59