XE24S100
June 2006
Xecom XE24S100 the Smallest, Complete 2.4 GHZ FHSS Transceiver
Description
Models
The Xecom XE24S100 is a miniature 2.4 GHz Spread
Spectrum transceiver. It includes all RF hardware and a
XE24S100D: Includes DipoleAntenna connector
micro-controller to manage the communications link.
XE24S100DK-C:XE24S100CDevelopmentKit
The micro-controller manages all communications task
XE24S100DK-D:XE24S100DDevelopmentKit
including configuration, data packaging, and Frequency
Hopping. The result is a complete wireless data
Features
communications solution.
1.55” x 0.9” x 0.12” Leadless Surface-Mount package
Utilizes globally available 2.4 GHz ISM band
The XE24S100 package is unique because of its size
Control and Configuration with AT commands.
(less than 1.4 square inches), its leadless surface-mount
design, and the availability of an on-board chip antenna.
254 unique node addresses plus 254 unique Group
IDs allow multiple large networks to coexist.
No competitive products can offer a solution as flexible,
convenient, and easy to integrate,
Programmable Transmit Power Output, max. 100 mW
Typical Receiver Sensitivity -87 dBm
There are two XE24S100 models; the XE24S100C with
Typical Throughput rate 20,000 bps
the on-board chip antenna and the XE24S100D with
dipole antenna connector. The dipole antenna improves
Obstructed signal range 150 feet (XE24S100D)
range while the chip antenna lowers system cost and
Multiple Low Power Operating modes
simplifies integration. Development Kits are available
SensorOnAir TM (patent pending) allows direct
for each version. A pin-compatible, higherer power
connection of sensors to the Smart Transceiver
variant is also available, the XE24St00, for applications
Count-Off TM (patent pending) allows the host node to
with longer range requirements.
download the status of all nodes in under 10 seconds.
FCC Part 15 Modular Certification
XE24S100 Block Diagram
XECOM
(1)
XE24S100
XE24S100 MECHANICAL SPECIFICATIONS
0.100”
18
1
0.100”
bottom
10
9
XECOM
(2)
XE24S100
Using the XE24S100 Power Saving Modes
The XE24S100 includes three low power operating
RF MONITOR MODE: RF Monitor Mode holds
modes (Sleep, Power-Down and RF Monitor) to
the transceiver in power down mode for an interval
allow the host application to make maximum use of
set by Register S110. The transcevier then
the available power. The #P command selects the
activates, turns on its receiver, and checks the air
transceiver operating mode when it is not actively
for incoming messages. If no messages are
transmitting or receiving data. Below are
detected within 200 milliseconds, the transceiver
descriptions of all of the available selections.
returns to power down mode. If carrier is detected,
the transceiver completes the transaction before
IDLE: In Idle Mode all XE24S100 circuits are
returning to power down mode. S110 selects an
powered and available for immediate action. This
interval of 1 to 60 seconds. Power consumption in
includes the RF receiver which actively monitors
RF Monitor Mode ranges from 1 to 10 milliamps
the air for an incoming communications request.
depending upon the activation interval.
SLEEP: In Sleep Mode all XE24S100 circuits are
AT COMMAND CONTROL
powered-down to minimize power consumption.
The XE24S100 power saving modes are controlled
The XE24S100 cannot accept commands or
by the AT#Pn command as described below.
respond to incoming RF communications requests
from Sleep mode. Any input on TXD will wake the
AT#P0
Select Idle mode.
transceiver and return it to the previous mode,
AT#P1
Select Sleep Mode.
either the Idle or Power-Down Mode Current
draw in Sleep Mode is less than 50 microamps.
AT#P2
Select Power-Down Mode.
AT#P3
Select RF Monitor Mode
POWER-DOWN: In Power-Down Mode all RF
circuitry is shut down but the communications
RF MONITOR INTERVAL: S110=n
controller remains active to accept AT commands.
Values of 1 to 60 set the RF Monitor interval in 1
The XE24S100 cannot respond to incoming RF
second increments
communications requests. If a transmit RF or
receive RF command is received, the XE24S100
can activate the RF section in under 200
microseconds. Current draw in Power-Down
Mode is less than 2 milliamps.
XECOM
(3)
XE24S100
XE24S100 PIN CONFIGURATION
XE24S100
DIO2
1
18 DIO0
DIO3
2
17 DIO1
VCC
3
16 GND
/RTS
4
15 ADC1
/CTS
5
14 ADC0
RXD
6
13 Reserved
TXD
7
12 N/C
N/C
8
11 N/C
N/C
9
10 N/C
top view
SIGNAL
PINS
DESCRIPTION
DIO2
1
DIO2 may be programmed as either a digital input or digital output. It connects directly to
the communications controller in the XE24S100.
DIO3
2
DIO3 may be programmed as either a digital input or digital output. It connects directly to
the communications controller in the XE24S100.
VCC
3
3.3Volt power for the XE24S100.
/RTS
4
Request to Send provides hardware flow control from the host system. The host system
drives /RTS high to signal the XE24S100 to temporarily stop the flow of data on RXD.
/CTS
5
Clear to Send provides hardware flow control from the XE24S100. The XE24S100 drives
/CTS high to signal the host to temporarily stop the flow of data on the TXD.
RXD
6
Received Data is the data output from the XE24S.
TXD
7
Transmit Data is the data input to the XE24S
N/C
8-12
No Connection
Reserved
13
This Pin is reserved for future use
ADC0
14
Analog Input 0 to the XE24S100 communications controller. ADC0 connects to an
internal 12-bitAnalog to Digital Convertor. ADC0 may also be configured as a digital
input if no analog inputs are required.
ADC1
15
Analog Input 1 to the XE24S100 communications controller. ADC1 connects to an
internal 12-bitAnalog to Digital Convertor. ADC1 may also be configured as a digital
input if no analog inputs are required.
Ground
16
Common voltage reference for the XE24S100.
DIO1
17
DIO1 may be programmed as either a digital input or digital output. It connects directly to
the communications controller in the XE24S100.
DIO0
18
DIO0 may be programmed as either a digital input or digital output. It connects directly to
the communications controller in the XE24S100.
XECOM
(4)
XE24S100
ABSOLUTE MAXIMUM RATINGS
VCC
3.6Volts
Storage Temperature
-55 O C to +125 O C
Operating Temperature Range
-40 O C to +85 O C
WARNING: Exceeding any of these ratings will void the warranty and may damage the device
XE24S100 ELECTRICAL SPECIFICATIONS
Parameter
Min
Typ
Max
Units
Comments
VCC
3.0
3.3
3.6
Volts
ICC
200
mA
Transmit (100 mW output)
30
mA
Receive Mode
20
mA
Idle Mode
1
10
mA
RF Monitor
1.0
mA
Power-Down Mode
0.050
mA
Sleep Mode
Output Power:
4.5
100
mW
50 Ohm Load
Wireless Receive Sensitivity
-87
dBm
Range thru Physical Obstructions
150
feet
500 mW output
Frequency Hopping Channels
TBD
Frequency Band
2.400
2.4835
GHz
Antenna Output Impedance
50
Ohms
Latency
TBD
mSec
Voh
2.4
Volts
Vol
0.8
Volts
Vih
2.0
Volts
Vil
0.4
Volts
XECOM
(5)
XE24S100
XE24S100 TYPICAL CONNECTION DIAGRAM
Antenna
3.3 V
C1 C2 C3
C4
C5
DIO2
DIO0
L1
DIO3
DIO1
VCC
GND
Host
/RTS
ADC1
Serial
/CTS
ADC0
I/F
RXD
Reserved
TXD
N/C
N/C
N/C
N/C
N/C
XE24S100
top view
Parts List for XE24S100Typical Connection Diagram
Reference
Designation
Qty
Description
C1
1
Capacitor, Electrolytic, 100 ufd, 10 Volts
C2,C4
2
Capacitor 0.1 ufd, 10Volts
C3,C5
2
Capacitor 47 pfd, 10 Volts
L1
1
TBD
Antenna *
1
50 Ohm, 1/4 Wave;
XECOM
(6)
XE24S100
XE24S100 COMMUNICATIONS CONTROLLER
An internal micro-controller serves as the XE24S100
Command Line - Commands may be strung
communications controller. This micro-controller
together in a single command line of up to 30
manages the host interface, manages the wireless
characters. Commands in the command string are
link, and formats data for the RF communications.
executed in the sequence they appear. An
“ERROR” response will be issued if the command
HOST INTERFACE
buffer is overfilled and none of the commands will
The XE24S100 has two primary system interfaces;
be executed.
the serial interface and the direct sensor interface
supported by SensorOnAir™. The communications
Omitted Parameters - Many commands include a
controller manages both interfaces.
parameter which determines the function setting.
When the command parameter is omitted from the
Serial Interface
command string, it is assumed to be a 0.
The XE24S100 supports a 4-line serial interface.
Control and configuration of the transceiver takes
Result Codes - Result codes are normally issued
place through the serial interface using modem-like
after each action. Result codes may be provided as
AT commands. The serial data rate is configurable
full words, numeric codes, or may be disabled.
from 1200 to 115.2K bits per second. The supported
When numeric result codes are chosen, each result
serial interface signals are listed below.
code ends with a Carriage Return. Full word result
codes are preceded and followed by a Line Feed
TXD - Transmit Data; input for commands and for
and Carriage Return.
Data to be transmitted on the wireless link.
Disconnect Sequence - A 3-character sequence
RXD - Received Data; the output for received RF
initiates a disconnect of the wireless link.
The
data and responses to AT commands.
sequence “~~~” is assigned to disconnect the link.
/RTS - Request to Send, hardware flow control
DIRECT CONNECTION OF SENSORS
input. The host raises /RTS to tell the
SensorOnAir ™ permits sensors to be connected
XE24S100 to stop passing data on RXD.
directly to the XE24S100 without an application
/CTS - Clear to Send, is the hardware flow control
controller.TheXE24S100 communicationscontroller
output. The XE24S100 raises /CTS to stop
controls the operation of the sensors.
data input on the TXD lead.
Sensor I/O Lines ™
XE24S100 AT Command Format
SensorOnAir ™ controls the operation of 6 I/O lines.
Each command follows a standard command
This includes 2 analog inputs,ADC0 andADC1, and
format as described below. Commands are
4 digital I/O lines, DIO0, DIO1, DIO2, and DIO3.
accepted at data rates from 1200 to 115,200 bps.
ADC0 and ADC1 are connected to a 12-bit analog
The default serial data rate is 9600 bps and is
to digital converter and use a 2.5 volt reference
changed using register S23.
derived from VCC as their reference voltage. The
digital I/O lines can be programmed to act as either
Command Prefix - Each command, except A/,
inputs or outputs.
begins with the AT prefix. The "A" and "T" may be
either both upper case or both lower case but cannot
be of different cases. The prefix identifies parity of
the commands sent to the XE24S100 by comparing
the parity bits of the "A" and the "T" characters.
XECOM
(7)
XE24S100
XE24S100 COMMUNICATIONS CONTROLLER (continued)
Configuring for Sensor Operation
AT#IxxxDn? - This command allows the status of
All SensorOnAir ™ functions are performed by the
Digital I/O “n” on node address “xxx” to be
XE24S100 communications controller. Modem-like
read remotely
AT commands loaded through the serial interface,
program the functions of the analog and digital lines.
AT#IxxxDn=z - This command allows the state of
The configuration is then stored in Flash memory.
digital output “n” on node address “xxx” to
This allows the XE24S100 to be programmed and
be set remotely. When z=0 the output is set
then installed in the application.
to a logic low; when z=1 the output is set to
a logic high.
SensorOnAir Commands ™
WIRELESS COMMUNICATIONS
Below is a list of the commands and registers used
ThecommunicationscontrollermanagestheRFLink
to program SensorOnAir ™ operation.
including the frequency hopping algorithm; collision
avoidance, node addressing, and data packets. The
S107 - Defines the I/O lines. The two analog inputs,
communications controller supports point-to-point,
ADC0 and ADC1, can also be defined as
point-to-multipoint or multipoint networks.
digital I/O lines if needed. The four digital
Carrier Sense Multiple Access (CSMA)
lines, DIO0, DIO1, DIO2, and DIO3; can
be set as either inputs or outputs. The value
To prevent collisions between nodes, the XE24S100
of this register is stored in flash memory.
uses a Carrier Sense Multiple Access protocol at
each transceiver. All nodes listen for link activity
AT&IAn? - This command allows a local host to
before initiating a session. If a wireless link already
read the value of Analog Input “n.”
exists, the transceiver waits until that session is
complete before initiating a new wireless link.
AT&IDn? - This command allows a local host to
read the status of Digital I/O “n.”
Data Packets
Data presented by the system host is placed into
AT&IDn=z - This command allows a local host to
packetsbytheXE24S100communicationscontroller
set the condition of the digital output “n.”
for transmission across the wireless link. These
When z=0 the output is set to a logic low;
packets provide addressing and error correction for
when z=1 the output is set to a logic high.
the wireless communications. The received data
AT#IxxxAn? - This command allows the value of
is extracted from the packets before being passed
Analog Input “n” on node address “xxx” to
to the serial interface.
be read remotely.
XECOM
(8)
XE24S100
XE24S COMMUNICATIONS CONTROLLER (continued)
Sample FileTransfer
Transmitter
Receiver
TXD
RXD
TXD
RXD
Description
AT#T01<cr>
Initiate File Transfer
:<cr>
FILE<cr>
Link Established
abc...z
abc...z
File Data
3 sec pause in data
A718<cr>
Checksum at End of File Transfer
OK<cr>
File Transfer Successful
or
ERROR<cr>
Error Detected in File Transfer
Note: In the above example that the file transfer is assumed to be completed when three seconds pass with
no data being presented to the TXD input on the serial port.
Multipoint Network
System designers can create a point-to-multipoint network with up to 253 remote nodes. The master node
is assigned address 1. The remote nodes use addresses 2 to 254. For efficient network operation, Count-
Off™ allows the master node to poll the entire network in under 10 seconds.
Count-Off™ permits the master node in a point-to-multipoint system to quickly check the status of all
network nodes. It creates a temporary time division multiplexing scheme which permits each node to
report its status without the handshaking sequence normally required for a wireless data exchange.
Count-Off™ is initiated by the AT#C command, from the host system. The master node broadcasts the
command to all network nodes. Upon receipt of the command each remote node initializes an internal
timer. Then in sequence by address each node transmits an 8-byte status message. The status message
is programmed with the AT#E: or AT#E= command. The status byte is passed to the host system in the
correct sequence upon receipt of the Count-Off message from the master node.
Using Count-Off™ network reporting will be completed in less than 10 seconds. Based on the status
information the host can then elect to service any of the remote nodes.
COUNT-OFF™SEQUENCE
Node 1
Node 1
Node 1
Node n
Node 2
Node n
Node 2
Node n
Node 9
Node 3
Node 9
Node 3
Node 9
Master
Master
Master
Node 8
Node 4
Node 8
Node 4
Node 8
Node 7
Node 5
Node 7
Node 5
Node 7
Node 6
Node 6
Node 6
T 0 - Master Broadcasts
T 1 - Node 1 Transmits
T 2 - Node 2 Transmits
T n - Node n Transmits
Count-Off Initiation
8-Byte Status
8-Byte Status
8-Byte Status
Count-Off Complete
XECOM
(9)
XE24S100
XE24S100 COMMUNICATIONS CONTROLLER (continued)
USER CODE
TheTexasInstrumentsMSP430F148microcontrollerservesasthecommunicationscontrollerintheXE24S100
transceiver modules; however, the communications functions do not fully utilize the capabilities of the
microcontroller. Xecom has created a way for our customers to run their simple remote monitoring application
on the transceiver’s communications controller saving the complexity and cost of incorporating a separate
microcontroller.
Has shown in the software block diagram above, the User Code interfaces to the rest of the XE24S code
through the User Code Support block. The User Code Support block interfaces to the AT command engine
and serial interface and supports other features such as sub routine calls.
To prevent the User Code from interfering with the communications responsibilities of the controller, the
User Code must be written in User Tasks. Each User task is a simple state machine that can quickly
complete its function. A full description of the requirements of the User Tasks can be found in the “XE24S
User Application Programmers Guide.
XECOM
(10)
XE24S100
AT COMMANDS
An asterisk indicates the factory default
&IDn? Read Local Digital Input “n” - read the
status of the local digital inputs.
A
Answer Command - force response to a link
request
n=0 Read input DIO0
n=1 Read input DIO1
Dn Initiate a Wireless Link - attempt to
connect with the transceiver at address n.
n=2 Read input DIO2
n=3 Read input DIO3
En Echo Characters -
n=4 Read DIO4 (ADC0 set as digital I/O)
n=0 Characters not Echoed
n=5 Read DIO5 (ADC1 set as digital I/O)
n=1 Characters Echoed *
&IDn=z Set Local Digital Output “n” - sets
In
Product Identification -
the state of the local digital outputs. z=0 sets
n=0 Display Product Code
the output to a logic low; z=1 to a logic high.
n=1 Display Product Name
n=0 Set output DIO0
n=2 Display Model Number
n=1 Set output DIO1
n=3 Display Copyright
n=2 Set output DIO2
n=4 Display Firmware Revision
n=3 Set output DIO3
Qn Result Code Display -
&Kn Flow Control - selects the flow control used
n=0 Display Result Codes *
between the system host and the XE24S100
n=1 Do not Display Result Codes
n=0 Flow Control Disabled
Sn= Set Value of Register Sn
n=3 RTS/CTS, hardware Flow Control
n=4 XON/XOFF, in-band Flow Control
Sn? Read Value of Register Sn
&V View Active Configuration - sends the