Run this command to see if 25xx flash is detected, with your RPi properly wired. sudo ./flashrom -p linux_spi:dev=/dev/spidev0.0,spispeed=32768 if the Bios is still not recognized with Detect, then reverse the jumper in the mini SPI programmer and reverse the clamp on the motherboard’s Bios. There is no risk of short circuit normally. The reason is simple: on most systems, the flash shares a common power rail with many other components on the board, which draw a lot of current. Further, if you accidentally provide too much voltage or cause an overcurrent, you could fry those other components but if there is diode protection, you’ll only fry the boot flash (and it is very easy to replace, if you have good soldering skills). chip information can be customized, this datasheet is about USB to serial port and USB to Infrared Adapter SIR. NOTE: On some systems, higher speeds will be unstable. On those systems, try lower speed like spispeed=4096 or even spispeed=2048 which should, in most cases, work just fine but it will obviously be slower. The spispeed=32768 setting works just fine on most setups if you use short wires, within 10cm.

Do not connect the power source until your chip is otherwise properly wired. For instance, do not connect a test clip that has power attached. Standard USB print port for upgrading the original print port printer, compatible with the relevant USB specifications. The chip is still readable and writable, so I guess is not totally fried (if so, peace, I'm just experimenting in a world I don't know at all, as said I fount this laptop in the trash). With how I arrived at my solution, I do wonder if I could have been helped by adding the datasheet-recommended 0.47 uF capacitor as you describe above.

Conclusion

Optional: customize the vendor ID, product ID, serial number, etc. via an external low-cost serial EEPROM. First, connect just the Pico to your computer with a micro-USB cable. Mount it like any other USB flash drive. If it isn’t detected, you might need to press the BOOTSEL button while you plug it in (this forces it into the bootloader mode). CH341SER.ZIP - archive containing driver files and serial API and library (you don't need specific API for standard serial port, but it contains some special functions to get IC version etc.) Hi, reading chinese datasheet for CH341 and at end of chapter 5.2 硬件说明 (Hardware description) is stated:

As per usual, this is a tutorial on the internet. Do anything you see here at your own risk. I am not responsible if anything goes wrong. Do this for chips mounted to a breadboard. Ignore this section if you’re flashing a chip that is already soldered to a mainboard. Use a hot air rework station, set to about 330-340C. The reason for the higher temperature is because air doesn’t conduct heat as efficiently as an iron, so you must use a higher temperature. You should put lots of rosin flux above the IC. Do not hold the nozel too close to the board. The diameter of the nozel should be slightly higher than the length of the chip. Apply even heat, at high air flow. connect the SOIC8 clip to the Bios (8-pin SPI memory chip); it is near a JSPI1 connection (see image below). The program recognizes that the programmer is connected. CH341SER_LINUX.ZIP - Linux driver source code for serial port (don't need this one, it's already included in kernels)

Recommendations

Internal flashing means that the host CPU on your system can re-program the SPI flash, using an on-board SPI programmer (which all boards have). You do this from Linux, with flashrom.