User's Manual

Table Of Contents

9XCite Wireless OEM Module – Product Manual v1.0

Pinout Signal Overview

The interface signals are available through the 11-pin header. All pins operate on VCC CMOS

levels. Five signals that are commonly used in applications are:

• DI (pin 4 – Data In)

• DO (pin 3 – Data Out)

• VCC (pin 10 – Power)

• GND (pin 11 – Ground)

•

(pin 1 – Clear-to-Send)

The remaining 6 pins (SLEEP (PWRDN),

, , RX LED, /PWR, ) may be used for

additional functionality. Go to the “XCite Advanced Programming & Configuration Manual” for

more detailed information about module pinouts.

Application Circuit

Figure 2. Application Circuit – connection to host processor

Serial Data

Data enters the 9XCite Module through the DI Pin as an asynchronous serial signal. The signal

should idle high when no data is being transmitted.

Each data packet consists of a start bit (low), 8 data bits (least significant bit first) and a stop bit

(high). The following figure illustrates the serial bit pattern of data passing through the module.

Figure 3. UART data packet 0x1F (decimal number “31”) as transmitted through the 9XCite Module

The 9XCite Modules transfer 7 or 8 bits over-the-air [Selectable using BI Parameter]. The start

and stop bits from the UART signal are not transmitted, but are regenerated on the receiving

module.

DI (Data In) Buffer

Once serial data has entered the 9XCite Module through the Data In (DI) Pin, the data is stored

in the DI Buffer until it can be transmitted.

Once the first byte of data enters the DI Buffer, the module begins to initialize the RF channel

(unless RF data is being received). In the case where the module is receiving RF data, the serial

data is stored in the DI Buffer. When the DI Buffer has only 17 bytes of memory left, the 9XCite

Module de-asserts (high)

to signal to the host device to stop sending data. re-asserts

once the DI Buffer has at least 35 bytes available in memory. Once in the DI Buffer, the data is

packetized for transmission. [The packet structure is broken down on the next page.]