Sierra Wireless AIRPRIME WISMO218 - Manual (Page 45)

WA_DEV_W218_PTS_002 Rev 006 April 29, 2010 45
Product Technical Specification &
Customer Design Guidelines Interfaces
3.8. General Purpose Input/Output
The AirPrime WISMO218 provides up to 3 General Purpose I/Os. They are used to control any
external device such as an LCD or a Keyboard backlight.
These GPIOs offer the possibility to read the pin state whatever their direction may be.
3.8.1. Pin Description
Table 13: GPIO Pin Descriptions
Signal Pin Number I/O I/O Type Reset State
GPIO1 24 I/O 2V8 Pull up
GPIO3 16 I/O 2V8 Pull up
GPIO5 19 I/O 2V8 Pull down
Caution: GPIO2 is dedicated for WISMO_READY and is not open as GPIO purpose for customer use.
GPIO4 is dedicated for TX burst indication and is not open as GPIO purpose for customer use.
When GPIO5 is used as a general purpose output, it is necessary to have an external pull up resistor
connecting to a 2.8V source. Resistance value depends on the current drain required by the
application side.