Self-made high voltage parallel programmer using single chip microcomputer AVR

　　I just had a few locked M8s a while ago. I guess even RESET was disabled. These chips can no longer be restored through the download line. In order to reduce losses, I searched on the Internet. It turns out that the fuses of AVR chips are reprogrammable, unlike OTP fuses, which cannot be modified after being configured once. It just doesn't require a high-voltage programmer (12v, not suitable for ISP download lines). I looked on Taobao.com and found that the price of finished high-voltage programmers is not cheap. Besides, I don't use them often. Usually, an ISP download line is enough. It is also convenient. You don't need to remove the chip from the target board to program. According to the current situation, it is imperative to make a simple high-voltage programmer by yourself. In order to promote our DIY spirit, I found some information and software and prepared to make a high-voltage parallel programmer by myself. After a while of tinkering, the programmer is finally done. Now I share the production process and some experience with you for reference by interested friends.

　　Description: High-voltage parallel programming can restore most of the locked chips to factory default, especially for chips that are disabled by reset. This high-voltage parallel programmer uses an M8 as the main control chip, converts various PC instructions and programming data sent through the serial port, and then programs the target chip. Currently, it can directly support the programming of M8 and M16. Since M16 programming is not required, the schematic diagram has been modified.

　　The final schematic is as follows:

　　With the schematic diagram, all that was left was to draw the board and make the board. So I worked late into the night and the finished PCB-3D diagram was as follows:

　　Then, there are two options. The first is to make the board yourself, using the thermal transfer method. The disadvantage is that it is more laborious because I don’t have a printer. If you want, you can also use a universal board. After all, the circuit is relatively simple. The second is to send the PCB file to a professional circuit board manufacturer. The disadvantage is that it costs RMB. As for where to find it, you can find it by searching on Taobao. I used the second option. I found all the components while the PCB was still not back. The PCB board that was sampled is as follows:

　　The picture shows several pieces connected together, just put them apart and pretend.

　　The next step is to solder the components. It is useless to talk about it, but it is practical to do it. Solder the horizontal and shorter components first:

　　Re-soldering large components:

　　The finished effect is as follows:

　　Haha, it looks very small; [page]

　　However, the programming cannot work at this time, because it has no "soul". Next, we use the ISP line we made before to inject the "soul" of the programmer into the main control IC-M8.

　　The one with USB port in the picture is the USB-ISP cable made last time. Below is the temporary AVR minimum system board. The first step: after connecting, open the software and configure the fuse, as shown in the figure:

　　Step 2: Click to load Flash, select the folder where the Hex file is located and open it;

　　Step 3: Click Auto; the Hex file will be written into the MCU as shown in the figure:

　　The progress bar shows the burning progress.

　　After writing, remove the chip and insert it into the board just soldered. After connecting, open the M8HVPRO software. The first step is to click Set Port if your serial port number is not the default COM1, set the port number corresponding to your serial number, and then close and restart. The third point: click Communication Detection. If it shows that the connection is successful! Then congratulations, your high-voltage programmer is ready.