Firmware is loaded at 38,400 bits per second (bps).
The K3 Utility determines the K3's initial RS-232 speed by sending MCU commands and analyzing responses, changes the K3 to 38,400 bps to load firmware, and changes the K3's speed back to the original value after firmware is completely loaded. If the firmware load operation is interrupted, the original speed may not be restored. Upon restart, the K3 Utility will find the K3 at 38,400 bps.
The K3 commands used to change RS-232 speed require interaction with operational MCU firmware. A K3 in its "boot load" state, indicated by a dim LED panel with "MCU LD" and a red Tx light, communicates only at 38,400 bps, and that's where it is left after firmware load is complete.
The Test Communications button displays the current RS-232 speed.
If the K3's RS-232 speed needs to be changed, use the K3 CONFIG:RS-232 menu item.