[MM32 eMiniBoard Review] Give feedback on this board

littleshrimp

[MM32 eMiniBoard Review] Give feedback on this board [Copy link]

 

I feel very good after getting this board. I think it should be the best domestic development board I have ever used.

The board is small in size and compact in design, and can basically meet the common functions.

Onboard USB emulator, the emulator integrates USB to serial port function

Contains EEPROM, FLASH memory, buzzer, and also integrates CAN transceiver

It is also convenient to find and download the corresponding tools on the official website. Except for the difficulty in installing the IAR debugger, running routines went smoothly.

The music of Zhu Bajie carrying his wife on his back is played automatically when the power is turned on, which is quite magical. This gives people a very good feeling.

However, no matter how good something is, there will always be some shortcomings. I personally feel that these are not big problems. I will just bring them up for your reference.

1. Maybe it's because this board is relatively new. The MB-025 shown on the package and the silk screen of the board is the same as the schematic diagram, and the corresponding chip is F032. At the beginning, I directly searched for information according to F032.

Later I found out that F032 does not have USB, but the official schematic and the real thing both connected the USB data cable to the USB port. Then I went to the evaluation application page and looked at the silk screen of the main control chip carefully, and found that the model is MM32F0133.

2. If the SW1 and SW2 in the schematic diagram use symbols similar to the following, it should be easier to understand the conduction relationship of the switches. Otherwise, it will take some time to figure out how to turn them on.

Or you can draw a symbol similar to the real object, but it is better to give some directional hints, such as which one is the first leg, etc., or draw it asymmetrically like the real object.

I understand that SW1 is a single-pole double-throw switch, which is used to select whether to use a 120-ohm matching resistor. However, can you tell from the schematic diagram which side the switch should be moved to in order to use a 120-ohm resistor?

The correct answer is this. I analyzed the wiring of the actual diagram, but I'm not sure. I also measured it with a multimeter. Is it exactly the opposite of what I understood from the schematic?

I think this extra work is unnecessary.

After analysis, it is found that SW2 should be a double-pole double-throw switch. Turning it to the left is used to disconnect the connection between CAN_RX and SS. In this way, the SPI control pins corresponding to CAN_RX and U5 can be brought out through the pin header for other purposes.

Turn right to use CAN reception and implement SPI to U5 control at the same time

3. The following may not be a problem. When I buy chips, sometimes the source is unreliable. I dare not use the chip in the red box in the middle. I personally feel that a normal chip should have a granular surface like the one in the blue box.

It looks like it came out of the mold directly. The surface roughness of the FLAH chip in the red frame in the middle is uneven. Many times I think it is a silk screen that was re-printed after polishing. However, this chip should be directly obtained from the manufacturer. The possibility of it being a fake or refurbished one is very small, but I don’t know why this happens.

4. In the factory routine, when the pause button is pressed, the PWM does not update but does not stop output. Some netizens have mentioned the problem before. Sometimes the noise during the pause is quite loud.

w494143467

The host's observation is really careful! I just took a simple look at the development board and powered it directly. Maybe my hardware foundation is not good enough. I don't know whether the manufacturer did it right or not. I dare not comment. But after listening to the host's explanation, I can understand some of it, haha.

freebsder

The review was very careful. It is indeed inconvenient that the switch does not have a silk screen. I can't open the schematic every time.

okhxyyo

Free Trial Review of Lingdong MM32 eMiniBoard

Summary post: https://bbs.eeworld.com.cn/thread-1146791-1-1.html

zwk34

Good, I had to make a logo myself.