When a colleague was using the segment code screen, the screen display was abnormal. When DAC or OPA was opened for initialization, the screen display was incorrect and the brightness was abnormal.
Solutions:
1. First, I looked at the code configuration and found that with the code that enables OPA to connect DA output voltage, the screen will not light up, but there was no conflict between the pins before.
2. Could the chip run away? Blow the chip off again and solder it, it's not a chip problem.
3. Does the screen pin configuration conflict with the DAC and OPA? There is no conflict, not for this reason.
4. Check the hardware circuit. Finally, I found that the resistor connected to the analog power supply by the power supply was forgotten to be soldered. How could I forget to solder the resistor (wry smile). Wasted a lot of time on this mistake. . . . . .
Summarize the common ideas for debugging problems encountered in daily life (if you are a more sloppy person, you can refer to the methods):
1. If there is a problem, first look for the hardware. Problems are more likely to occur in the hardware. For example, the package 0402 is too small, or due to lack of welding experience, chip short circuit, virtual soldering, etc. Check content: First look at the main chip to see if the pins are soldered. If you are not sure, use flux to check the status (and then re-upload the program to check the status). After reading the chip, look at the capacitors and resistors. This needs to be looked at carefully, pay attention! ! ! Be sure to look at the schematic! ! !
2. If the reason is not 1, let’s check the program next. First check: Initialization, take a rough look at it and make sure everything you need has been initialized. If there is no problem, look carefully: start from the beginning, click on a specific initialization configuration, open the data sheet, and look at it. You need to be patient here, come on.