PNI CommBoard - Manual (Page 7)

PNI Sensor Corporation DOC#1018122 r02
PNI CommBoard User Manual Page 5
4 Set-Up
4.1 Communication Setup
The CommBoard‟s physical interface is USB, but it runs a virtual UART over the USB line.
As such, it is necessary to implement a virtual communication port (VCP) on the user‟s
computer. The CommBoard uses FTDI‟s FT232R USB-to-RS232 IC, and the driver for this
IC should be installed on your computer. This driver can be found on FTDI‟s website at:
http://www.ftdichip.com/Drivers/VCP.htm .
After installing the VCP driver and plugging in your PNI device, connect the CommBoard to
your computer using a USB-to-mini-USB cable. The USB line provides power to the
CommBoard and the device-under-test. The UART should be configured as shown below.
Table 4-1: UART Configuration
Parameter Value
Baud Rate 115200
Number of Data Bits 8
Start Bits 1
Stop Bits 1
Parity none
Figure 4-1 shows how a computer connects to a PNI device mounted on the CommBoard.
On the computer side, the user will send commands using an ASCII terminal program such
as HyperTerminal or Realterm. Alternatively, Matlab or a similar application that outputs
ASCII can be used. These all will use a Virtual Comm Port to place their UART commands
on the USB line of the computer. On the PNI CommBoard, the UART commands either are
translated into SPI commands or I
2 C commands using the CommBoard‟s CPU, or sent
directly to the PNI device. Whether the UART commands are translated into SPI or I
2
C, or
fed directly into the PNI device, is established by the jumpers, discussed in Section 4.1.