- TXD: sender, usually expressed as its sender, then another when normal communications equipment RXD.
- RXD: Receive-side, generally expressed as their receiver, then another when normal communicationsequipment TXD.
When normal communications will always take their devices TXD RXD!
Spontaneous self-closing: As the name suggests, is to receive its own transmitted data is receivedtheir own TXD RXD, used to send and receive test itself is normal. Also known as loop-back test.
The module has been integrated MAX3232 serial conversion circuit, and with a two DB9 male and one female head, no matter what your equipment is male or female can be connected with the module, theBluetooth pairing can not respond to AT commands, paired then as a transparent serial transmission of data, the module requires an external power supply, a 3.3V module integrated LDO, the power from themodule's power input TTL interface, TTL interface, TXD, RXD for the HC06 module's serial port directly to the output, when the module can not be set higher than 115200bps reset via DB9 connectors, you can use USB to serial interface to re-set by the lower baud rate
