EncoderCAT / xCAT  -  CAT command example

The examples here are taken from the Yaesu FTdx101D CAT manual.
Other Yaesu radios appear to use the same codes.

Kenwood radios use a similar system.

EncoderCAT's encoders modify the current level of their assigned radio parameter.

Three RS232 transactions are needed for each change. ( RF Power 70 > 75 as example )

       EncoderCAT increments or decrements the value according to encoder direction and step setting.

The oscilloscope tracings below show EncoderCAT transmissions in yellow and radio response in purple.

RS232 settings are 38400 baud, 2 stop bits, no parity, 8 bits/char.

The oscilloscope has decode switched on and set to serial data, ASCII presentation.
The decoded characters appear at the bottom of the image.

In this example, the whole sequence takes 5ms.
The implied speed capability of 200 encoder  notches per second well exceeds realistic encoder click rates!!