I managed to fry my LPC1768 when it got hit by a stray wire. I replaced the chip- don’t try this at home, kids; i’m an electronics engineer lol. I re-burned the bootloader as described on this site. FlashMagic verifies the burn as OK, but it still isn’t working. The USB isn’t detected by Windows, the LCD backlight is on but no text. the red LEDS flash very briefly when I power it on and then the green LEDs turn on steady. This is different from before i flashed it so something took.
I check the Vcc and reset lines onthe chip. I’ve re-flashed 3x with the same results and used both the edge and main bootloaders from github. It’s a AZSMZ Mini if that makes a difference.
It seems that if it will burn ok, that the hardware is working enough to get the usb up. I did check the USB wiring from the connector to the chip. THere’s not much more there than IO lines and those shouldn’t affect the USB function.
I’m out of ideas. Any thoughts?
Imported from wikidot
Once you’ve flashed the bootloader, you also need to flash the firmware, did you do that ?
It doesn’t need the firmware.bin loaded in order to be detected by Windows. I did try it but the behavior does not change if there’s a SD card inserted with firmware.bin or not.
I finally got windows to detect it by flashing the bootloader from github /triffid/LPC17xx-DFU-Bootloader. It still makes no apparent attempt to load the firmware.bin. It’s detected in device manager as Unknown Device > (!)Smoothie. I’ve used the card on this computer before so it should have already had the driver installed. I tried manually installing first the 1.0 driver and then the 1.1 driver but neither work. "Windows could not find driver software for your device.
Thanks
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You definitely the firmware loaded in order to be detected by Windows. Unless you put it into DFU mode, but that shouldn’t happen by itself.
You definitely need to get the bootloader to flash the firmware ( the file gets renamed ).
With the triffid bootloader windows detects an Unknown Device > Smoothie. With the bootloader from the install guide here nothing is detected.Both are named “DFU-Bootloader.hex” and there are no details on gethub about their functionality . I’ve tried 2 versions of firmware.bin and 2 different micro-sd cards. Tried Win 8 then 10 and they both show unknown devices. the card being in or out makes no visible difference on either the board or windows.
Is the card supposed to be FAT or FAT32? I tried both but not all permutations of bootloaders, firmware, cards, and formats. one is 2gb and one is 16. the 16gb was working before the problem.
Thanks so much!
Hey.
The SD card should be FAT32.
At this point, if it still doesn’t work, I’d contact the seller for help and/or a replacement.
Cheers.
Hi,
I’ve managed to replace LPC 1769 at home. (also had problem with it like no control of digipots). Flashed bootloader and firmware. Now everything is working just fine.
Did you happen to take a few pictures of the process ? I’d love for it to be documented a bit so people know it’s a possible option
No. But still have old chip without legs on my table.
I’ve used scalpel to cut off legs under the magnifier. Then plain soldering iron ($20) with sharp tip (used file) to pick up the rest of the legs from the board. Cleaning the pads. All under the magnifier.
Most difficult - positioning the new chip. Used scotch tape. Small pieces. One by one. Side by side.
Flux, and then just careful soldering leg by leg under the magnifier. Without solder. Whatever left on the pads was enough.
FTDI cable and Flash Magic.
Done.
I’ve been hacking away at it without much luck. I did make one interesting discovery. I finally found another bootloader for the LPC1768- a slightly hacked version of the NXP bootloader (which I can’t find anywhere). When i load that one, the board will boot and windows will detect it as a storage device and I can see the firmware.bin that’s on the microSD card. That tells me that the USB side and the microSD is working. I put the smoothie bootloader back on and windows does not attempt to load it (no ‘found new hardware’ chirp)
I’m pretty much at a loss at the moment. I did order some 2gb microSDs in case there’s some compatibility issues.
I have been in contact with the seller and he’s done what he can- sent firmware and boot loader, indtructions and pics for burning the bootloader, ect.
i was going to take some pics, then decided it wasn’t really useful. There are tons of much better chip replacement videos on youtube. I prefer the chip-quik method. The stuff is amazing!
(can’t post links so google H0m_d52m1DU)
The kit is a little $$ for a one shot deal so surganova’s surgery method may be better for a one-off use. The ‘sharp tip’ scares me as the pads are tiny and fragile. Screw one up and you’re done for. Solder wick is better, but more $ if you don’t use it otherwise. You’ll likely need it anyway when you accidentally bridge 2 (or 3 or 4!) pins and need to remove the extra solder.
Aligning the new chip is the hardest part. I align it and hold it in place with one finger. tack one corner. recheck that it didn’t move. you may be able to nudge it a little when tacked. otherwise heat the tacked pin and try again. Then tack the opposite corner. recheck. then solder the rest.
Cheapest price I found for the chip in the US is $10.70 from digikey, PN: 568-4796-ND