Don’t have friends that are using Photons. I wanted to try and shoot my shot with JTAG, but i honestly would need help with that
not sure if this is going to help you but here is a discussion on using the jtag interface: Re-flash bootloader & firmware to bricked Photon
@AlexTheLion2016, before you go any further, I suggest you take out (or get) your digital multimeter. With the USB adapted plugged in and your Photon plugged into an empty breadboard, measure the voltage between GND and Vin and also GND and the 3V3 pin and report back your findings.
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If D7 is not dimly lit when the Photon is powered up, then it’s probably not a corrupted bootloader issue. I suspect hardware damage, having to do with overtaxing something on the Photons with the servo setup. (I did not look at the Fritzing diagram in detail – I’m not a Fritzing Fan ;^) ). (For the first Photon – if it does Dim D7 on power up, then it could probably be recovered.)
Y’know – maybe there’s something wrong with the servo, that results in too much power being pulled. That is a total WAG, but I can’t figure out what else might be going on, if you’re using exactly the same servo as was used in the Instructable.
(later) I just noticed something in the picture of the servo from the Instructable: https://cdn.instructables.com/FE3/R71C/JKIKCGM8/FE3R71CJKIKCGM8.LARGE.jpg Does the mention of wire colors mean that there are two versions of the servo, with different wiring (Hitec, JR)?
Finally – and I’m really grasping at straws here – did all three Photons die on the same breadboard, in the same position hole-wise?
ParticleD.
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Just to be clear, the D7 led is dimmed and RGB led is off ? If so, would be a bootloader issue (as the support mentioned before). That happens to me mucho more frecuent that I wanted; I’ve perform the procedure as the documentation suggests and @rickkas7 (thanks man) gave me the proper commands to perform in order to unlock the “flash protection”.
I;m not quite sure if the procedure is exactly the same between electron and photon, but I use to perform the next steps (even today happened to me):
The connections has to be like :
JTAG ELECTRON
SWCLF D6
SWDIO D7
GND GND
The jtag usb connector has to be connected to the USB port on your PC (it would be obious but …). Also the photon has to be connected via usb charger as well and the GND is now “shared”.
I typed the next commands (I use mac, and you have to follow the steps to install openocd):
cd /usr/local/share/openocd/scripts
openocd -f interface/stlink-v2.cfg -f target/stm32f2x.cfg -c "telnet_port 4444"
In a separated command prompt type :
telnet localhost 4444
Trying 127.0.0.1...
Connected to localhost.
Escape character is '^]'.
Open On-Chip Debugger
and then :
init
reset halt
stm32f2x unlock 0
reset halt
program <route to your bootloader>/bootloader-electron.bin verify 0x08000000
flash protect 0 0 0 on
reset halt
At this point you have to get the next output :
target halted due to debug-request, current mode: Thread
xPSR: 0x01000000 pc: 0xfffffffe msp: 0xfffffffc
** Programming Started **
auto erase enabled
target halted due to breakpoint, current mode: Thread
xPSR: 0x61000000 pc: 0x20000046 msp: 0xfffffffc
wrote 16384 bytes from file ./bootloader-electron.bin in 0.822450s (19.454 KiB/s)
** Programming Finished **
** Verify Started **
target halted due to breakpoint, current mode: Thread
xPSR: 0x61000000 pc: 0x2000002e msp: 0xfffffffc
verified 16384 bytes in 0.138109s (115.851 KiB/s)
** Verified OK **
The last steps has to be flash the system firmware and the sketch as the documentation mentions.
Hope it helps.