cj7hawk

Hi Paul, the uart1 is the same port that goes to the receiver, so you have to unplug the receiver to access the ISP interface. We can successfully reprogram the CG035 but we can't undo the damage caused by a bad flash from the VAST software. AOSENMA have done something to prevent people copying their code, and I think it looks for a serial in the CPU and won't work unless that is present, and every CG035 has a different one. If you backed up your configuration before you flashed it, it can be unbricked, but only if backed up first, since your code is unique to your CG035. It's a copy protection system. The manufacturer has advised that we can write new software for the CG035 ourselves if we wish, and has confirmed that the uart1 is how they reprogram their quads as well, but they won't give us the software to fix it. It's a shame. Some others are still trying to get the software out of them. So if anyone wants to try updating their firmware, the first step should ALWAYS be to back up the existing firmware first using the ISP, then flash using the VAST software, then back up the new firmware if successful also using the ISP and save these backup files. We're still looking for a solution for everyone. In the mean time, they are selling new boards for around $80 or so. Which might explain why they aren't too keen on helping us solve the problem since the boards are worth about $20.

Hi All, I'm making progress on unbricking - Have managed to get the bootloader working - but I don't have a copy of the binary firmware. If anyone has it, please contact me and send me a copy - Anyway, to help others who have bricked their controllers, and can't get them to recognize.... And to help those upgrading to make a backup first. First, the reset button you might have heard about doesn't help much and won't do anything about a firmware failure - the reset switch just goes to a general input on the processor. The true boot selector is the two pins at the back of the PCB, although most probably just have two holes where the pins go. There should be around 3.3v difference between the two - The negative side is a pulldown to BOOT0 on the processor. Solder two pins in here and install a jumper, or just short them together for a second or so while you insert the battery. At this point, the processor will go into BOOTLOADER mode. Remove the UART1 cable from the main board ( it's the one that goes to the receiver ) - If you do this, then make a plug to go into it, and break it out to GND, TXD and RXD. The pins are 5v tolerant. Now connect this to a TTL uart interface ( you can get them on Ebay - About $5 each or so... Plug into USB ). - Then download the ISP programmer from http://gd32mcu.21ic.com/en/index It's the Gigadevice ISP programmer ( In System Programmer ) - Yes, they often use a strange serial port. We're not using it. It's OK. Now... Power up the quad in BOOTLOADER mode. The lights underneath will flash slowly and it will make a slow beeping sound. Connect the UART cable to UART1 as per above. Run the ISP software. Select the serial port that was assigned to the USB uart adapter ( or whatever serial port you're using ). Connect... It should recognize the chip immediately and tell you it's ID, then will tell you that it's not write or read protected. THEN go to the next page... UPLOAD ( from quad down to you ) a COPY of the existing firmware from the device ( if it's good ) before reflashing. Even upload the bad one and store it with a suitable filename if it's bad. Once you've made backup copies in both .HEX and .BIN ( make both for convenience later ) - then get a copy from a good quad with the same board revision, and DOWNLOAD it to your quad. You can also restore an earlier version. This is the ONLY known way to unbrick your quad. Oh yeah, if you used a jumper instead of just shorting the pins on power-up, then remember to remove it before resetting, or you won't realize why nothing is working. Interesting note: You can set a serial terminal program to 115200 baud and watch the output from the quad when it starts up. It will tell you what's going on. Hope this helps someone else - I'm still looking for a backup copy for firmware for the 1.1version board, so if anyone makes a good backup, and can supply it, please let me know. David.