Your attendance machine should support this com/rs485. Under normal circumstances, both are compatible and the interfaces are the same. You buy a com port line to connect the computer and the attendance machine, and then connect it in the attendance software with com 1 port and baud rate 1 1520. If not, try one by one.
If your attendance machine really doesn't support this com port, but the computer only has com port, which is also rs232, so it can't be directly connected with the attendance machine, then you can buy a connector from rs232 to rs485, preferably above 50 yuan, and install it on the com port of the computer, and then you can connect the attendance machine with rs485.