Datasheet

2009-2012 Microchip Technology Inc. DS70594D-page 73
dsPIC33FJXXXMCX06A/X08A/X10A
5.0 FLASH PROGRAM MEMORY
The ds
PIC33FJXXXMCX06A/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 allows a dsPIC33FJXXXMCX06A/X08A/X10A
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
program memory word; 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 1: This data sheet summarizes the features
of the dsPIC33FJXXXMCX06A/X08A/
X10A family of devices. However, it is not
intended to be a comprehensive refer-
ence source. To complement the infor-
mation in this data sheet, refer to Section
5. “Flash Programming” (DS70191) in
the “dsPIC33F/PIC24H Family Refer-
ence Manual”, 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