PIC24HJ128GP206-I Datasheet, PDF (55/286 Pages) Microchip Technology – High-Performance, 16-Bit Microcontrollers

PIC24HJXXXGPX06/X08/X10
4.0 FLASH PROGRAM MEMORY
Note:
This data sheet summarizes the features
of this group of PIC24HJXXXGPX06/X08/
X10 devices. It is not intended to be a
comprehensive reference source. To com-
plement the information in this data sheet,
refer to the “PIC24H Family Reference
Manual”. Refer to the Microchip web site
(www.microchip.com) for the latest
PIC24H Family Reference Manual
sections.
The PIC24HJXXXGPX06/X08/X10 devices contain
internal Flash program memory for storing and execut-
ing 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
PIC24HJXXXGPX06/X08/X10 device to be serially
programmed while in the end application circuit. This is
simply done with two lines for programming clock and
programming data (one of the alternate programming
pin pairs: PGC1/PGD1, PGC2/PGD2 or PGC3/PGD3,
and three other lines for power (VDD), ground (VSS) and
Master Clear (MCLR). This allows customers to manu-
facture boards with unprogrammed devices and then
program the digital 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.
4.1 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 4-1.
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 4-1:
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
© 2007 Microchip Technology Inc.
DS70175F-page 53