PIC12F519 Microchip Technology, PIC12F519 Datasheet - Page 49

• Manufacturer Part Number: PIC12F519
• Description: 8-Bit Flash Microcontroller
• Manufacturer: Microchip Technology

www.DataSheet4U.com
8.9
If the code protection bit has not been programmed, the
on-chip program memory can be read out for
verification purposes.
The first 64 locations and the last location (OSCCAL)
can be read, regardless of the code protection bit
setting.
The last memory location can be read regardless of the
code protection bit setting on the PIC12F519 device.
8.10
Four memory locations are designated as ID locations
where users can store checksum or other code
identification numbers. These locations are not
accessible during normal execution, but are readable
and writable during program/verify.
Use only the lower 4 bits of the ID locations and always
program the upper 8 bits as ‘0’s.
8.11
The PIC12F519 device can be serially programmed
while in the end application circuit. This is simply done
with two lines for clock and data, and three other lines for
power, ground and the programming voltage. This
allows users to manufacture boards with unprogrammed
PIC12F519 device and then program the PIC12F519
device just before shipping the product. This also allows
the most recent firmware, or a custom firmware, to be
programmed.
The PIC12F519 device is placed into a Program/Verify
mode by holding the RB1 and RB0 pins low while rais-
ing the MCLR (V
ming specification). The RB1 pin becomes the
programming clock, and the RB0 pin becomes the
programming data. Both RB1 and RB0 pins are Schmitt
Trigger inputs in this mode.
After Reset, a 6-bit command is then supplied to the
device. Depending on the command, 14 bits of program
data are then supplied to or from the device, depending
if the command was a Load or a Read. For complete
details of serial programming, please refer to the
“PIC12F519 Memory Programming Specification,”
(DS41316).
A typical In-Circuit Serial Programming connection is
shown in Figure 8-12.
© 2007 Microchip Technology Inc.
Program Verification/Code
Protection
ID Locations
In-Circuit Serial Programming™
PP
) pin from V
IL
to V
IHH
(see program-
Preliminary
FIGURE 8-12:
External
Connector
Signals
Data I/O
CLK
+5V
V
0V
PP
To Normal
Connections
To Normal
Connections
TYPICAL IN-CIRCUIT
SERIAL PROGRAMMING
CONNECTION
PIC12F519
V
V
MCLR/V
RB1
RB0
V
DS41319A-page 47
DD
SS
DD
PIC12F519
PP