OpenOCD PIC32 Programmer
The instructions posted here can potentially ruin your RPI if you messed up the GPIO connections. Do this at your own risk.
OpenOCD together with RPi GPIO is used to program the PIC32 chip for those who doesn't have the Pickit2/3 programmer.
The following steps were performed within RPi using Raspbian image.
Install required software
sudo apt-get install libjim-dev libtool automake texinfo
Make /usr/src directory writable to users
sudo chmod a+rw /usr/src
Download OpenOCD
cd /usr/src
git clone git://git.code.sf.net/p/openocd/code openocd-code
Compile and install
cd openocd-code
git checkout fe97fab -b rpi
./bootstrap
./configure --enable-maintainer-mode --disable-werror --enable-sysfsgpio
make
sudo make install
Create configuration files
sudo sh -c 'cat>/usr/local/share/openocd/scripts/interface/rpi.cfg<<EOF
#
# Config for using RaspberryPi'"'"'s expansion header
#
# This is best used with a fast enough buffer but also
# is suitable for direct connection if the target voltage
# matches RPi'"'"'s 3.3V
#
# Do not forget the GND connection, pin 6 of the expansion header.
#
interface sysfsgpio
# Each of the JTAG lines need a gpio number set: tck tms tdi tdo
# Header pin numbers: 19 26 21 23
sysfsgpio_jtag_nums 10 7 9 11
# At least one of srst or trst needs to be specified
# Header pin numbers: TRST - 15
sysfsgpio_trst_num 22
EOF'
sudo sh -c 'cat>/usr/local/share/openocd/scripts/board/pic32mx150f128b.cfg<<EOF
set CPUTAPID 0x14D06053
source [find target/pic32mx.cfg]
EOF'
sudo sh -c 'cat>/usr/local/share/openocd/scripts/board/pic32mx764f128h.cfg<<EOF
set CPUTAPID 0x1440B053
source [find target/pic32mx.cfg]
EOF'
It is preferable that the PIC32 is programmed outside of the circuit using the recommended minimal circuit:
Connect the RPi P1 header pins to the target PIC32 using the following table:
| JTAG | P1 Header | PIC32MX1xxB | 64 pin PIC32 |
|---|---|---|---|
| tck | 19 | 17 | 27 |
| tms | 26 | 22 | 23 |
| tdi | 21 | 16 | 28 |
| tdo | 23 | 18 | 24 |
| trst | 15 | 1 | 7 |
| VDD | 17 | 13,28 | 10,19,26,38,57 |
| VSS | 25 | 8,19,27 | 9,20,25,41 |
RPi GPIO Pinout
Blank chips can be easily programmed using OpenOCD. But chips that are already programmed with the JTAG disabled in the main code (normally used to release the IO's used by JTAG) are tricky. The following bash script is needed to program both new and used chips:
NOTE: Replace the BRD_CFG value with pic32mx764f128h.cfg if you are programming the original PICnc board
cat>pic32openocd<<EOF
#!/bin/sh
TRST_GPIO=22
BRD_CFG=pic32mx150f128b.cfg
if [ -z \$1 ]
then
echo "firmware file is missing!"
echo "Usage: pic32openocd <hexfile>"
exit
fi
echo \$TRST_GPIO > /sys/class/gpio/unexport 2>/dev/null
echo \$TRST_GPIO > /sys/class/gpio/export
echo "low" > /sys/class/gpio/gpio\${TRST_GPIO}/direction
echo "1" > /sys/class/gpio/gpio\${TRST_GPIO}/active_low
openocd -f interface/rpi.cfg -f board/\${BRD_CFG} &
sleep 1
(
echo 'reset init'
sleep 1
echo "high" > /sys/class/gpio/gpio\${TRST_GPIO}/direction
echo "0" > /sys/class/gpio/gpio\${TRST_GPIO}/active_low
sleep 1
echo pic32mx unlock 0
sleep 1
echo reset init
echo program \$1
) | nc localhost 4444 > /dev/null
EOF
chmod +x ./pic32openocd
sudo cp pic32openocd /usr/local/bin
Do not disable JTAG using the configuration bits:
#pragma config JTAGEN = ON // Enable JTAG. Do not turn off!
Once disabled, only ICSP programming is allowed.
rpi@rpi:~$ sudo /usr/local/bin/pic32openocd test.hex
Open On-Chip Debugger 0.7.0-dev-00207-gfe97fab (2013-03-31-09:49)
Licensed under GNU GPL v2
For bug reports, read
http://openocd.sourceforge.net/doc/doxygen/bugs.html
Info : only one transport option; autoselect 'jtag'
SysfsGPIO nums: tck = 10, tms = 7, tdi = 9, tdi = 11
SysfsGPIO num: trst = 22
adapter_nsrst_delay: 100
jtag_ntrst_delay: 100
Info : SysfsGPIO JTAG bitbang driver
Warn : gpio 22 is already exported
Info : This adapter doesn't support configurable speed
Warn : writing srst failed
Info : JTAG tap: pic32mx.cpu tap/device found: 0x14d06053 (mfg: 0x029, part: 0x4d06, ver: 0x1)
Info : accepting 'telnet' connection from 4444
Info : JTAG tap: pic32mx.cpu tap/device found: 0x14d06053 (mfg: 0x029, part: 0x4d06, ver: 0x1)
target state: halted
target halted in MIPS32 mode due to debug-request, pc: 0xbfc00000
Info : device id = 0x14d06053 (manuf 0x029 dev 0x4d06, ver 0x01)
Info : flash size = 3kbytes
pic32mx is already unlocked, erasing anyway
pic32mx unlocked.
INFO: a reset or power cycle is required for the new settings to take effect.
Info : JTAG tap: pic32mx.cpu tap/device found: 0x14d06053 (mfg: 0x029, part: 0x4d06, ver: 0x1)
target state: halted
target halted in MIPS32 mode due to debug-request, pc: 0xbfc00000
Info : JTAG tap: pic32mx.cpu tap/device found: 0x14d06053 (mfg: 0x029, part: 0x4d06, ver: 0x1)
target state: halted
target halted in MIPS32 mode due to debug-request, pc: 0xbfc00000
** Programming Started **
auto erase enabled
Info : device id = 0x14d06053 (manuf 0x029 dev 0x4d06, ver 0x01)
Info : flash size = 128kbytes
Info : Padding image section 5 with 125400 bytes
target state: halted
target halted in MIPS32 mode due to target-not-halted, pc: 0xa000088c
target state: halted
target halted in MIPS32 mode due to target-not-halted, pc: 0xa000088c
target state: halted
target halted in MIPS32 mode due to target-not-halted, pc: 0xa000088c
target state: halted
target halted in MIPS32 mode due to target-not-halted, pc: 0xa000088c
target state: halted
target halted in MIPS32 mode due to target-not-halted, pc: 0xa000088c
target state: halted
target halted in MIPS32 mode due to target-not-halted, pc: 0xa000088c
target state: halted
target halted in MIPS32 mode due to target-not-halted, pc: 0xa000088c
target state: halted
target halted in MIPS32 mode due to target-not-halted, pc: 0xa000088c
target state: halted
target halted in MIPS32 mode due to target-not-halted, pc: 0xa000088c
target state: halted
target halted in MIPS32 mode due to target-not-halted, pc: 0xa000088c
target state: halted
target halted in MIPS32 mode due to target-not-halted, pc: 0xa000088c
target state: halted
target halted in MIPS32 mode due to target-not-halted, pc: 0xa000088c
target state: halted
target halted in MIPS32 mode due to target-not-halted, pc: 0xa000088c
target state: halted
target halted in MIPS32 mode due to target-not-halted, pc: 0xa000088c
target state: halted
target halted in MIPS32 mode due to target-not-halted, pc: 0xa000088c
target state: halted
target halted in MIPS32 mode due to target-not-halted, pc: 0xa000088c
Info : Padding image section 7 with 880 bytes
Info : Padding image section 8 with 2148 bytes
target state: halted
target halted in MIPS32 mode due to target-not-halted, pc: 0xa000088c
wrote 131072 bytes from file test.hex in 40.309155s (3.175 KiB/s)
** Programming Finished **
shutdown command invoked
Untar the following file:
https://drive.google.com/uc?id=0B4Qqa1lYhaVBZ3p6RFZ0WC00elE&export=download
rpi@rpi:~$ sudo tar xvf openocd.tar.gz -C /