5
To dump the first 256 bytes of program storage (which starts at
location 0x200) you'd write:
app3 -m 100 -d pgm com1
If you wanted to erase the chip (not necessary when programming)
and also wanted to verify that it was blank, you can issue these two
commands:
app3 -e com1
app3 -b com1
Internals
The APP-II is actually a PIC18F252 that operates at 20MHz. You
can find documentation for this device at the Microchip Web site.
However, the APP-III environment makes programming a little
different. In particular:
•
Your program starts at location 0x200.
•
Port B pin 7 is not generally available for your use.
•
Port B pull up resistors are enabled briefly on reset –
however, if you want them enabled, you must enable them
in your own program.
Although you can use the serial port in your own programs, you
must be able to configure the two serial port pins for serial I/O to
program. Therefore, we don't recommend you use the serial port
for anything other than a serial port.
The chip will not allow you to change certain fuse settings (notably
the code protect options and the clock selection).