Integration Guide

WIT2410

4.1. Interfacing to 5 Volt Systems

The modem interface signals on the WIT2410 are 3.3 volt signals. To interface to 5 volt

signals, the resistor divider network shown below must be placed between the 5 volt

signal outputs and the WIT2410 signal inputs. The output voltage swing of the WIT2410

3.3 volt signals is sufficient to drive 5 volt logic inputs.

4.2. Evaluation Unit and OEM Module Differences

The evaluation unit has an RS-232 transceiver that translates RS-232 level signals to 3.3

volt signals for input into the OEM module inside the evaluation unit. A typical

schematic is shown in Appendix 7.5. The OEM module does not have any type of RS-

232 transceiver and cannot handle the RS-232 voltages. This allows the OEM module to

be easily integrated into any 3.3 volt system without any logic signal translation. In order

for the OEM module to function properly several pins need to be driven low or tied to

ground. Pin 5 (RTS) and pin 6 (SLEEP) need to be pulled to ground on the 16-pin male

header. If you have the OEM module interfaced to an RS-232 transceiver, RTS and DTR

need to be pulled high on the transceiver side. In the evaluation unit, RTS and DTR are

pulled high on the transceiver side so the evaluation unit will work with these signals not

connected.

4.3. Three Wire Operation

The WIT2410 can be operated in a three wire configuration using just TxD, RxD and

Ground. To operate the WIT2410 in this configuration, the Sleep and RTS signals must

be tied to ground. These signals are pulled up on the WIT2410 module and if left

disconnected will put the radio into sleep mode and RTS will be deasserted.

The WIT2410 does not support software flow control (XON/XOFF). Thus when using a

three wire configuration, there is no flow control. The radio configuration and/or the

application must insure the transmit and receive buffers do not overflow. The WIT2410

has a 2048-byte transmit buffer and a 1024-byte receive buffer. For example, the default

settings for the base slot size and hop duration are 08H and 90H respectively. The 08H

base slot size allows the base to send 32 bytes of data per hop. The 90H hop duration

provides a 10ms hop dwell time. These default settings provide a base throughput of

2200 

4300 

From 5v

Output

To 3.3v Input