This file contains some information that I learned after buying and disassembling a modbus pulse counter from the F&F company. The model of the device is MAX-MB-LI-4LO.
BOM
| Designator | Marking | Type | Manufacturer | Description | Datasheet | Notes |
| ST8S005K6TC | ST8S005K6TC | STMicroelectronics | MCU | mirror | ||
| S485C8 | ST485C | STMicroelectronics | Low power RS-485/RS-422 transceiver | mirror | ||
| USB62 | USB6B1 | STMicroelectronics | Data line protection | mirror | ||
| LH04 354T X | LTV-354T | LiteON | Photocoupler | mirror | 1 per channel |