8
4. OPERATION
Being a communication device, Model 840 will
operate with user intervention based on signals
received from a Curtis motor controller. Upon
initial power-up, the instrument will go through a self-
diagnostic routine in which all display elements will be
illuminated for 1 second and then blanked for 1 second.
The LCD will then display “all asterisks” until the first
message is received. The information on the display will
then be controlled by the Curtis motor controller.
