Datasheet

© 2009 Microchip Technology Inc. DS70287C-page 73
dsPIC33FJXXXMCX06/X08/X10
5.0 FLASH PROGRAM MEMORY
The ds PIC33FJXXXMCX06/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
V
DD range.
Flash memory can be programmed in two ways:
1. In-Circuit Serial Programming™ (ICSP™)
programming capability
2. Run-Time Self-Programming (RTSP)
ICSP allows a dsPIC33FJXXXMCX06/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: 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 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 by blocks (or ‘rows’) of
64 instructions (192 bytes) at a time or by single pro-
gram memory word; and the user can 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 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: This data sheet summarizes the features
of the dsPIC33FJXXXMCX06/X08/X10
family of devices. However, it is not
intended to be a comprehensive reference
source. To complement the information in
this data sheet, refer to Section 5. “Flash
Programming” (DS70191) in the
“dsPIC33F Family Reference Manual”,
which is available from the Microchip web
site (www.microchip.com).
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