Datasheet

Using the Applications Software
5-4
The Soft Mode Control group includes checkboxes for toggling the state of the
DC servo (DC
), common-mode servo (CM), overload (OL), and GPO1 through
GPO4 control bits. An empty checkbox sets the state of the corresponding bit
to 0. Clicking on the checkbox will set the corresponding control bit to 1. Click-
ing on the checkbox again will clear the control bit, setting it to 0.
The Hard Mode Control group is not utilized for the PGA2500EVM. Instead,
these controls are configured using switch SW1 on the PGA2500EVM.
The Gain group includes a slider for setting the gain of the PGA2500. Simple
text displays are provided for the programmed gain in dB, as well as the gain
and bus data shown in hexadecimal data format. A Readback button is pro-
vided with a corresponding text display, and may be used to read and display
the control word value in hexadecimal data format. The Readback function is
provided mainly as a software and hardware diagnostic function, because it
allows the user to determine if the PGA2500 control word is being pro-
grammed correctly. This function can be used to debug hardware and cable
connection problems, or to help identify possible software compatibility is-
sues.
Finally, a Clear button is provided, which sets all of the data bits in the
PGA2500 control word to 0.