Ampro Corporation LITTLE BOARD 5001451A - Manual (Page 36)

2-18
Table 2-16. USB Port 1 Pinout
J4 Pin # Signal Name Function
1 USBPWR1 USB1 +5 Volt Power
2 USBP-1 USB1 Data-
3 USBP+1 USB1 Data+
4 USBGND1 Ground
5 SHIELD1 Cable Shield for USB1
Table 2-17. USB Port 2 Pinout
J5 Pin # Signal Name Function
1 USBPWR2 USB2 +5 Volt Power
2 USBP-2 USB2 Data-
3 USBP+2 USB2 Data+
4 USBGND2 Ground
5 SHIELD2 Cable Shield for USB2
Infrared (IrDA) Interface
The Little Board P6d infrared interface provides for a two-way wireless communications port using
infrared as a transmission medium. The Little Board P6d IrDA interface supports both SIR (Serial
Infrared) and FIR (Fast Infrared) standards . The SIR standard allows serial communication at
baud rates up to
115K Baud. The FIR standard allows data rates up to 4Mbps.
Requirements for an IrDA Interface
On the Little Board P6d module, the IrDA physical link hardware consists of an IR transmit
encoder and IR receiver decoder. To implement an IrDA port, the OEM must supply an IR
transducer, which consists of the output driver and IR emitter for transmitting, and the receiver IR
detector. Particular IR transducers may require additional external components.
The IrDA port uses the second serial port to drive its internal encoder/decoder. When using the
IrDA interface, you cannot use serial 2 as an RS232, RS485, or RS422 port.
IrDA Connector (Part of Utility J19)
There are two popular implementations of Fast IR. One uses a separate receive line capable of
receiving at the higher data rate (up to 4 Mbytes/second). The other is implemented with a mode
control line. When the IR port is set for high speed, the mode select line (IRMODE) is high. This
switches the external transceiver to high speed mode. The IrDA port pinout is listed in Table 2-18.