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Related Manuals for Laird AC4868-250
Summary of Contents for Laird AC4868-250
- Page 1 1 . 4 E R S I O N Downloaded from Elcodis.com electronic components distributor...
- Page 2 Limited Warranty, Disclaimer, Limitation of Liability For a period of one (1) year from the date of purchase by the OEM customer, Laird Technologies warrants the OEM transceiver against defects in materials and workmanship. Laird Technologies will not honor this warranty (and this warranty will be automatically void) if there has been any (1) tampering, signs of tampering;...
- Page 3 Downloaded from Elcodis.com electronic components distributor...
- Page 4 Version 1.3 9/18/07 - Internal Release. Version 1.4 9/5/08- Updated to Laird Technologies branding. Clarified Duty Cycle calculations. Updated information on client to client communications. Corrected Read Temperature Command to a max of 0x50. Updated Minimum Baud Rate Downloaded from Elcodis.com...
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Page 5: Table Of Contents
Table of Contents AC4868-250 Transceiver Module 1 EEPROM Parameters 26 AC4868-250 features 1 Dimensions 29 Overview 1 Mechanical Drawings 29 Specifications 2 Ordering Information 30 Product Part Number Tree 30 Pin Definitions 3 Developer Kit Part Numbers 30 Electrical Specifications 4... -
Page 6: Ac4868-250 Transceiver Module
Note: Unless mentioned specifically by name, the AC4868-250 modules will be referred to as the “radio” or “transceiver”. Individual naming is used to differentiate product specific features. The host (PC/Microcontroller/Any device to which the AC4868-250 module is connected) will be referred to as “OEM Host”. -
Page 7: Specifications
20 Pin Interface Connector Molex 87759-0030, mates with Samtec SMM-110-02-S-D RF Connector Telegartner J01341C0081, mates with any manufacturer’s MMCX style plug Antenna AC4868-250: MMCX Connector Serial Interface Data Rate Baud rates from 1200 bps to 57.6 kbps Power Consumption (typical) 10%TX... -
Page 8: Pin Definitions
P I N D E F I N I T I O N S The AC4868-250 has a simple interface that allows OEM Host communications with the transceiver. The table below shows the connector pin numbers and associated functions. The I/O direction is with respect to the transceiver. All inputs/outputs are 3.3VDC. -
Page 9: Electrical Specifications
S P E C I F I C A T I O N S E L E C T R I C A L S P E C I F I C A T I O N S T a b l e 3 : I n p u t V o l t a g e C h a r a c t e r i s t i c s High High Signal Name... -
Page 10: Theory Of Operation
M O D E S O F O P E R A T I O N The AC4868-250 has three different operating modes; Receive, Transmit, & Command Mode. If the transceiver is not communicating with another radio, it will be in Receive Mode actively listening for a beacon from the Server. If the Client determines that the beacon is from a server operating on the same RF Channel and System ID, it will respond by asserting In_Range Low. - Page 11 T H E O R Y O F O P E R A T I O N C o m m a n d M o d e A radio will enter Command Mode when data is received over the serial interface from the OEM Host and either the Command/Data pin (pin 17) is logic Low or the received data contains the “AT+++”...
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Page 12: Duty Cycle Limitations
TX time on, monitored over one hour and relative to a one hour period. Thus for the AC4868-250, the maximum “on” time in an hour cannot exceed six minutes. R A D I O O P E R A T I O N The AC4868 will transmit data whenever data is present on the serial UART. -
Page 13: Serial Interface
S E R I A L C O M M U N I C A T I O N S The AC4868-250 is a TTL device which can be interfaced to a compatible UART (microcontroller) or level translator to allow connection to serial devices. UART stands for Universal Asynchronous Receiver Transmitter and its main function is to transmit or receive serial data. -
Page 14: Oem Host Data Rate
S E R I A L I N T E R F A C E F i g u r e 3 : E v e n P a r i t y B i t Note: Enabling parity cuts throughput and the interface buffer in half. O E M H O S T D A T A R A T E The OEM Host Data Rate is the rate with which the OEM Host and transceiver communicate over the serial interface. -
Page 15: Interface Timeout / Rf Packet Size
S E R I A L I N T E R F A C E supported. For a baud rate to be valid, the calculated baud rate must be within ±3% of the OEM Host baud rate. If the Test pin (Pin 12) is pulled logic Low at reset, the baud rate will be forced to 9,600. T a b l e 7 : B a u d R a t e / I n t e r f a c e T i m e o u t RF Baud BaudL... -
Page 16: Half Duplex / Full Duplex
H A L F D U P L E X / F U L L D U P L E X When Half Duplex communication is chosen, the AC4868-250 will send a packet out over the RF whenever it can. This can cause packets sent by multiple transceivers at the same time to collide with each other over the RF. -
Page 17: System Throughput
S Y S T E M T H R O U G H P U T When operating as shown below, an AC4868-250 transceiver is capable of achieving the listed throughput. However, in the presence of interference or at longer ranges, the transceiver may be unable to meet the specified throughput. -
Page 18: Software Interface
A U T O C O N F I G P A R A M E T E R S The AC4868-250 has several variables that vary by RF mode and architecture. By default, Auto Config is enabled and bypasses the values stored in EEPROM and uses predetermined values for the given operating mode. Below is a list www.lairdtech.com... -
Page 19: Max Power
Max Power provides a means for controlling the RF output power of the AC4868. Output power and current consumption can vary by as much as ±10% per transceiver for a particular Max Power setting. Contact Laird Technologies for assistance in adjusting Max Power. -
Page 20: Timing Diagrams
IMING IAGRAMS A C 4 8 6 8 - 2 5 0 T I M I N G D I A G R A M S F i g u r e 4 : A d d r e s s e d M o d e w i t h T i m e o u t F i g u r e 5 : A d d r e s s e d M o d e w i t h F i x e d P a c k e t L e n g t h F i g u r e 6 : B r o a d c a s t M o d e w i t h T i m e o u t www.lairdtech.com... - Page 21 T I M I N G D I A G R A M S F i g u r e 7 : B r o a d c a s t M o d e w i t h F i x e d P a c k e t L e n g t h Downloaded from Elcodis.com electronic components distributor...
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Page 22: Hardware Interface
C T S The AC4868-250 has an interface buffer size of 256 bytes. If the buffer fills up and more bytes are sent to the transceiver before the buffer can be emptied, data loss will occur. The transceiver prevents this loss by asserting CTS High as the buffer fills up and taking CTS Low as the buffer is emptied. - Page 23 U P _ R e s e t UP_Reset provides a direct connection to the reset pin on the AC4868-250 microprocessor and is used to force a soft reset. For a valid reset, reset must be asserted High for a minimum of 11ms.
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Page 24: Configuring The Ac4868-250
AC4868-250 ONFIGURING THE The AC4868-250 can be configured using the CC Configuration Commands. The CC Commands can be issued using either Hardware or Software Configuration. To use Hardware Configuration, pin 17 of a transceiver must be asserted Low. Software Configuration can be used by entering AT Command Mode before issuing the CC Commands. -
Page 25: At Commands
A T C O M M A N D S The AT Command mode implemented in the AC4868-250 creates a virtual version of the Command/Data pin. The “Enter AT Command Mode” Command asserts this virtual pin Low (to signify Command Mode) and the “Exit AT Command Mode”... - Page 26 C O N F I G U R I N G T H E A C 4 8 6 8 - 2 5 0 T a b l e 1 1 : C o m m a n d Q u i c k R e f e r e n c e Command Name Command (All Bytes in Hex) Return (All Bytes in Hex)
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Page 27: Command Descriptions
C O N F I G U R I N G T H E A C 4 8 6 8 - 2 5 0 C O M M A N D D E S C R I P T I O N S E n t e r AT C o m ma n d M o d e Prior to sending this command, the OEM Host must ensure that the Command: 0x41 0x54 0x2B 0x2B 0x2B 0x0D... - Page 28 C O N F I G U R I N G T H E A C 4 8 6 8 - 2 5 0 B ro ad c a st Pa ck e t s The OEM Host issues this command to change the transceiver Command: 0xCC 0x08 Data1 operation between Addressed Packets and Broadcast Packets.
- Page 29 C O N F I G U R I N G T H E A C 4 8 6 8 - 2 5 0 W r i t e D i g it a l O u t p u t s The OEM Host issues this command to write both digital output lines to Command: 0xCC 0x23 Data1 particular states.
- Page 30 C O N F I G U R I N G T H E A C 4 8 6 8 - 2 5 0 EE PROM Byte Re ad Upon receiving this command, a transceiver will respond with the Command: 0xCC 0xC0 Data1 Data2 desired data from the addresses requested by the OEM Host.
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Page 31: Eeprom Parameters
High byte of interface baud. Always 0x00 Control 0 0x45 0x00 0x14 Settings are: 0xFF bit-7: Laird Technologies Use Only bit-6: DES Enable bit-5: Laird Technologies Use Only bit-4: Laird Technologies Use Only bit-3: Laird Technologies Use Only bit-2: Laird Technologies Use Only bit-1: RF Delivery... - Page 32 Broadcast packets are selected. API Control 0x56 0x00 0x43 Settings are: 0xFF bit-7: Laird Technologies Use Only bit-6: Laird Technologies Use Only bit-5: Unicast Only 0 = Disabled 1 = Enabled bit-4: Auto Destination 0 = Use destination address 1 = Use auto destination...
- Page 33 E E P R O M P A R A M E T E R S T a b l e 1 2 : E E P R O M P a r a m e t e r s EEPROM Length Parameter...
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Page 34: Dimensions
IMENSIONS M E C H A N I C A L D R A W I N G S Interface Connector - 20 pin OEM Interface connector (Molex 87759-0030, mates with Samtec SMM-110-02-S-D MMCX Jack - Antenna Connector (Johnson Components 135-3711-822) F i g u r e 9 : A C 4 8 6 8 - 2 5 0 ( w i t h M M C X c o n n e c t o r ) M e c h a n i c a l 2 0 p in h e a d e r , 0 .0 2 0 s q . -
Page 35: Ordering Information
RDERING NFORMATION P R O D U C T P A R T N U M B E R T R E E D E V E L O P E R K I T P A R T N U M B E R S All of the above part numbers can be ordered as a development kit by prefacing the part number with “SDK-”. -
Page 36: Compliancy Information
A P P R O V E D A N T E N N A L I S T The following antennas are approved for use with the AC4868-250 as identified. The OEM is free to choose another vendor’s antenna of like type and equal or lesser gain as a listed antenna and still maintain compliance. -
Page 37: Country Restrictions
C O M P L I A N C Y I N F O R M A T I O N C O U N T R Y R E S T R I C T I O N S The exclamation point included with the CE mark denotes that the equipment has restrictions in certain countries. -
Page 38: Declaration Of Conformity
D E C L A R A T I O N O F C O N F O R M I T Y Laird Technologies has issued a Declaration of Conformity for the AC4868-250M transceiver module concerning emissions, EMC, and safety. The Declaration of Conformity is a document that lists the product name and band of use and must appear in the OEM user’s manual. -
Page 39: Appendix I - Sample Power Supply
UPPLY Below is a simple switching power supply that provides enough current to easily power any Laird Technologies OEM module. It utilizes low cost, off the shelf components that fit into a small area. This supply has an input voltage range of +6 volts to +18 volts and will output +3.4 volts at 1.5 amps. -
Page 40: Schematic
A P P E N D I X I - S A M P L E P O W E R S U P P L Y S C H E M A T I C P C B L A Y O U T www.lairdtech.com Downloaded from Elcodis.com... - Page 41 A P P E N D I X I - S A M P L E P O W E R S U P P L Y Downloaded from Elcodis.com electronic components distributor...
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Page 42: Appendix Ii - 5V To 3.3V Levels
PPENDIX EVELS All inputs on the AC4868-250 are weakly pulled high via 10 kohm resistors. The AC4868-250 has 3.3V only inputs. Some of the most common voltage conversion methods are described below. V o l t a g e L e v e l C o n v e r s i o n I C ’ s This is the easiest and most efficient method.