ch340 usb not have DTR pin for programming pro mini. Simple hack
Connection:
CH340 ProMini
Vcc Vcc
Gnd Gnd
Rx Tx
Tx Rx
DTR DTR
My HiLetgo USB to TTL CH340 Module doesn't have a DTR Pin.
sdingman:
My HiLetgo USB to TTL CH340 Module doesn't have a DTR Pin.
That's why the OP pictures show the wire soldered directly to pin 15 (DTR) of the CH340 chip.