485 to TTL485 communication module normal two-phase automatic switching to send and receive data modbus

The drawing method of sharing the 485 to TTL module can be used normally. First draw the picture, then the drawing board, and finally the proofing is successful. The above picture is shared.
This is the test of the equipment in the picture below. Can realize data sending and receiving at 115200 speed. 600000 cannot be used normally. 
In terms of wiring: TX connects to TX, RX connects to RX. 
In terms of wiring: Anyway, there are clear instructions: A connects AB, connects B, RX connects to RX, TX connects to TX. 3.3-5V universal.
There is a wiring mark on the back.
Three resistors, 4.7K, and an 8050 NPN transistor patch. Can be welded. This can be accomplished with a fine-tipped soldering iron and tweezers.
Others are not difficult. The circuit is relatively simple. Realizes two-way automatic sending and receiving of data. Share it with friends in need.
The PCB files of 1206 and 0805 packages have been placed in the attachment.