Communication failure

cgu

Communication failure [Copy link]

The terminal prompts that the driver has a communication failure. The power supply is 24V5V and the communication line has been checked. The MAX491E RS422 has been replaced, but the problem remains the same. When the driver is powered on normally, after about 8 seconds, the relay (1) controlled by the 3rd pin of the MCU hears a traction sound. After 2 seconds, the relay (2) also tractions to charge the main drive capacitor with current limiting. The red indicator light is on and the green light flashes. Now, after power is turned on, it takes more than ten minutes for relay 1 to traction 2. The indicator light is also normal, but the system also reports a communication failure. How can I distinguish whether it is a problem with the system software or hardware or a problem with the driver itself? Is the chip DS26C32 related here? Please also tell me the pin conditions for the normal operation of the MCU. Thank you. DMD is the driver and CCP is the motherboard.

chunyang

First, confirm whether the timing of the closing action of relay 1 is consistent with that of a known normal device. If it is consistent, it means that the problem occurs after the closing of relay 1. Check the circuit action after the closing of relay 1 and analyze the reasons for the abnormal timing of the action of relay 2.

In most cases, this type of failure is a hardware problem. Software problems are only possible when an error code is written during an upgrade or firmware reflashing. If the software is not rewritten, this possibility can be completely ruled out.

cgu

chunyang posted on 2020-3-4 11:40 First confirm whether the timing of the pull-in action of relay 1 is consistent with that of the known normal device. If it is consistent, it means that the problem occurs after relay 1 is pulled in. ...

Thank you. There is only one such driver, the relay should be normal

cgu

Can you guide me to solve this problem? Master, please give me a price