USGlobalsat BU-353-S4 V1.0 (Mac) - Manual (Page 14)

13. BU-353S4 / BR-355S4 Product Pin Description
BU-355S4
PIN Number(s) Name Type Description
1 Vin P Main power supply to the BU-5353.
2,3 USB IF
USB IF to transmits channel for outputting
navigation and measurement data to user’s
navigation software or user written software.
4 GND P Ground.
LED RED
LEDOFF: Receiver switch off
LED ON: Receiver switch on
No fixed, Signal searching
LED Flashing: Position Fixed