Datasheet

 2013-2014 Microchip Technology Inc. DS70000689D-page 103
dsPIC33EPXXXGM3XX/6XX/7XX
5.0 FLASH PROGRAM MEMORY
The dsPIC33EPXXXGM3XX/6XX/7XX devices contain
internal Flash program memory for storing and
executing application code. The memory is readable,
writable and erasable during normal operation, over the
entire V
DD range.
Flash memory can be programmed in two ways:
• In-Circuit Serial Programming™ (ICSP™)
• Run-Time Self-Programming (RTSP)
ICSP allows for a dsPIC33EPXXXGM3XX/6XX/7XX
device to be serially programmed while in the end
application circuit. This is done with two lines for
programming clock and programming data (one of the
alternate programming pin pairs: PGECx/PGEDx), and
three other lines for power (V
DD), ground (VSS) and
Master Clear (MCLR
). This allows customers to
manufacture boards with unprogrammed devices and
then program the device 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
application can write program memory data as a double
program memory word, a row of 64 instructions
(192 bytes), and erase program memory in blocks of
512 instruction words (1536 bytes) at a time.
5.1 Table Instructions and Flash
Programming
The Flash memory read and the double-word
programming operations make use of the TBLRD and
TBLWT instructions, respectively. 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 the TBLPAG<7:0> bits 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
Note 1: This data sheet summarizes the features
of the dsPIC33EPXXXGM3XX/6XX/7XX
family of devices. It is not intended to be
a comprehensive reference source. To
complement the information in this data
sheet, refer to the “dsPIC33/PIC24
Family Reference Manual”, “Flash
Programming” (DS70609), which is
available from the Microchip web site
(www.microchip.com).
2: Some registers and associated bits
described in this section may not be
available on all devices. Refer to
Section 4.0 “Memory Organization” in
this data sheet for device-specific register
and bit information.
0 Program Counter
24 Bits
Program Counter
TBLPAG Reg
8 Bits
Working Reg EA
16 Bits
Byte
24-Bit EA
0
1/0
Select
Using
Table Instruction
Using
User/Configuration
Space Select