User's Manual

DS-RN24_V2 1/28/2009
809 University Avenue • Los Gatos, CA 95032 • Tel [phone] • [e-mail]
Digital I/O Characteristics
WARNING: Take care not to exceed the voltage limits to the VCC, TTL SERIAL, and GPIO pins. 0 negative
voltage or voltage exceeding 3.30 VDC can permanently damage the device!
• Use a 10KΩ series resistor on inputs
• GPIO sink current is 4mA max.
• Unused pins should float
2.7V ≤ VDD ≤ 3.0V Min Typ. Max. Unit
Input logic level LOW -0.4 - +0.8 V
Input logic level HIGH 0.7VDD - VDD+0.4 V
Output logc level LOW - - 0.2 V
Output logic level HIGH VDD-0.2 - - V
All I/O’s (except reset) default to weakpull down +0.2 +1.0 +5.0 uA
The RN24 can drive either UART signals on the TTL pins 8-11 or RS232 pins 13-16. WARNING: Driving the TTL
signals at RS232 levels can permanently damage the module. By default the module is configured to drive only
the RS232 pins. To drive the TTL signals you must remove the resistor R7. R7 can be found on the bottom of
the board, near the center.
Remove R7 to enable the UART
TTL signaling on pins 8-11.
This will disconnect pins 13-16
from the UART interface.