[Hangxin ACM32F070 supporting capacitive touch development board - dual-machine UART communication linkage Hangxin evaluation final part - part 2]

JohnMatthrew

[Hangxin ACM32F070 supporting capacitive touch development board - dual-machine UART communication linkage Hangxin evaluation final part - part 2] [Copy link]

This time, I pulled Arduino to do a communication linkage test

Without further ado, let's directly arrange for the wiring friend to connect and power on (UART2 is arranged, A2: Tx A3: Rx baud rate: 115200)

Finally, we can arrange communication with each other. Because the screen of Hangxin is customized, it displays temperature, humidity and power status. It is not very convenient to display the value of 11111111 we sent. After that, the display occupies part of the resources, but it doesn’t matter. The result is still very good. When you press the button, the other side receives what you want and lights up to indicate. You can watch the video to see the effect, it is quite good.

最终展示成果

********** ...

Finally, let me talk about our feelings halfway through. When we applied for this development board from Hangxin, there was actually quite a lot of information. We prepared for the question of whether we had enough time, and we didn't dare to make it too difficult. After all, it was in line with practical needs, and UART communication and transmission instructions were still very commonly used. Later, sometimes, I also took this development board to our workshop (working at room temperature of 75℃), and it could work very stably, supporting continuous work for 144 hours, and sending instructions to our console by pressing buttons. As a part of domestic MCU, Hangxin undoubtedly has a better reputation for this stability. When I worked abroad before, all the MCU materials were imported, either ST, MicroChip, NXP, Renesas, and TI. Now it seems that there are more choices.

*******Easter Egg Section********

When we were debugging the hardware, we found a place that could be corrected:

The function of this capacitor should be decoupling (it also plays a part in debouncing). When IO recognizes this button, once this capacitor is fully charged, it is equivalent to being directly pulled down, so there will be conflicts during recognition.

We have verified that removing this capacitor with a soldering iron will result in better recognition results.

hustjtj0806

When the IO recognizes this button, once the capacitor is fully charged, it is equivalent to being directly pulled down? ? I can't understand this circuit diagram. This capacitor is useless.

littleshrimp

The capacitor is connected to ground and when fully charged it should be at a high level. If the microcontroller is configured for pull-up there should be no problem.

JohnMatthrew

hustjtj0806 posted on 2022-11-10 06:32 When IO recognizes this button, once the capacitor is fully charged, this is equivalent to being directly pulled down? ? Some of this circuit diagram is incomprehensible, this...

This capacitor actually has no effect.

JohnMatthrew

littleshrimp posted on 2022-11-10 18:00 The capacitor is connected to the ground and when fully charged, it should be a high level. If the microcontroller is configured as a pull-up, there should be no problem.

Default drop-down

littleshrimp

JohnMatthrew posted on 2022-11-10 21:29 Default drop-down

If the button is pulled down by default, the corresponding pin will always be at a low level whether it is pressed or not.

JohnMatthrew

littleshrimp posted on 2022-11-11 07:34 If it is the default pull-down, whether the corresponding pin is pressed or not, it will always be at a low level

Yes, it maintains a low level, so it presents the same level as GND, so the multimeter beep will sound.

littleshrimp

JohnMatthrew published on 2022-11-12 23:32 Yes, it has been maintaining a low level, so it presents the same level as GND, so the multimeter buzzer will sound

So you need to configure the pin to pull up for it to work properly. Is the original routine configured to pull down?

JohnMatthrew

littleshrimp posted on 2022-11-13 11:05 So you need to configure the pin as pull-up to work properly. Is the original routine configured as pull-down?

Yes, you need to configure it manually