Encom ENC-900, Operating Manual

Page 1: ...el ENC 900 900 MHz Spread Spectrum OEM Transceiver Revision 1 00 February 23 2005 Encom Wireless Data Solutions Inc 7 640 42nd Ave N E Calgary Alberta T2E 7J9 Phone 403 230 1122 Fax 403 276 9575 http www encomwireless com ...

Page 2: ...testing of the transmitter is required as long as the 20 cm separation and co location requirements are observed Each new use of the module will however always need to be scanned for unintentional radiation from digital clocks etc All necessary calibration has been performed at the time of manufacture Any modification of the device after it leaves the factory is a violation of FCC rules Compliance...

Page 3: ...ot cause harmful interference and 2 This device must accept any interference received including interference that may cause undesired operation Contains TX FCC ID PLQENC900 Canada 3966A ENC900 S N XXXYYYZZZ MODEL ENC 900 Made in Canada The label should be printed or molded into the case using a type front and size that is readable with the unaided eye The FCC identification number is required Indu...

Page 4: ...ns where failure could result in damage to property or human injury or loss of life The electronic equipment described in this manual generates uses and radiates radio frequency energy Operation of this equipment in a residential area may cause radio interference in which case the user at his own expense will be required to take whatever measures necessary to correct the interference FCC Declarati...

Page 5: ...ult Codes display 20 W Connection Result 21 Z Reset and load stored configuration 21 C DCD Data Carrier Detect 21 D DTR Data Terminal Ready 21 F Load Factory Default Configuration 21 K Handshaking 22 S DSR Data Set Ready 22 V View Configuration 22 E Framing Error Check 22 W Write Configuration to Memory 22 Sxxx Read S register value 22 Sxxx yyy Set S register value 22 AT Command Result Codes 22 4 ...

Page 6: ...ming 33 S Register 119 Quick Enter to Command 34 S Register 120 RTS DCD Framing 34 S Register 121 DCD Timeout 34 S Register 123 Remote RSSI Reading 35 S Register 124 Master RSSI Reading 35 S Register 213 Packet Retry Limit 35 4 4 Diagnostics Statistics and Remote Control 36 4 4 1 Spectrum Analyzer Feature ATG 36 4 4 2 Statistics ATP 36 4 4 3 Remote Control and Diagnostics S101 5 37 A Modem Command...

Page 7: ... reliability 1 1 Features Key features of the ENC 900 include transmission within a public license exempt band of the radio spectrum1 this means that it can be used without access fees such as those incurred by cellular airtime a serial I O data port with handshaking and hardware flow control allowing the ENC 900 to interface directly to any equipment with an asynchronous serial interface 64 sets ...

Page 8: ... 4 provides complete details of all configuration parameters The Appendices including the Glossary of Terms are provided as informational references which you may find useful throughout the use of this manual as well as during the operation of the wireless modem Throughout the manual you will encounter not only illustrations that further elaborate on the accompanying text but also several symbols ...

Page 9: ...ENC 900 Operating Manual Chapter 2 Electrical Physical 5 ...

Page 10: ...PHYSICAL 2 0 Functional Block Diagram Transceiver Intrgrated Circuit Lowpass Filter Bandpass Filter Bandpass Filter Power Amplifier T R Switch Lowpass Filter 39 00 MHz Crystal Microcontroller Host Connector 32 768 kHz Crystal 6 10 Figure 1 Functional Block Diagram ...

Page 11: ...level input I 6 CTS RS 232 Clear to Send Active low TTL level output O 7 RTS RS 232 Request to Send Active low TTL level output I 8 DSR RS 232 Data Set Ready Active low TTL level output O 9 RSSI1 Receive Signal Strength Indicator 1 This output is the first of the three RSSI indicators to become active high as the signal strength increases O 10 RSSI2 Receive Signal Strength Indicator 2 This output ...

Page 12: ... In order to maintain compliance with the FCC modular certification it is necessary to mount the module in such a way that user is never closer than 20 cm to the antenna The manual for end users of the product must contain a warning about the 20 cm separation as outlined in the beginning of this manual Additionally the transceiver may not be co located with any other antenna or transmitter ...

Page 13: ...The most common method for installing the module is to run a short RF Jumper cable from the module s MCX connector to a reverse TNC bulkhead connector on the chassis of the equipment as shown in the following figure These cables can be purchased from Encom Wireless Data Solutions Inc RG174 Cable with MCX male connector and Reverse TNC bulkhead connector Reverse TNC Connector MCX female connector C...

Page 14: ...ode Master RSSI mode based on all received packets See Table 3 Data Mode Repeater During Sync Acquisition alternating 300ms ON Data Mode Repeater When Synchronized RSSI mode based on packets received from Remotes See Table 3 Data Mode Remote During Sync Acquisition alternating 300ms ON Data Mode Remote When Synchronized RSSI mode based on packets received from the Repeater or Master with which it ...

Page 15: ...RSSI the master takes into consideration all packets received from Remotes and repeaters Repeaters and Remotes only transmit back to the master when they have information to send Therefore if no data is coming back to the master then RSSI will never get updated at the master and the LED s will be off Signal Strength dBm RSSI1 RSSI2 RSSI3 95 50 duty cycle off off 90 on solid off off 85 on solid 50 ...

Page 16: ...ulated supply for Vcc Radio Do not directly feed a switching power supply into Vcc Radio Caution Using any other power supply which does not provide the proper voltage or current could damage the ENC 900 module 2 5 DC Characteristics Characteristic Min Typ Max Units Supply Voltage 3 80 V Transmit Current at 1W 900 mA Receive Current 28 mA Sleep Current 1 mA ...

Page 17: ...ENC 900 Operating Manual Chapter 2 Electrical Physical 13 ...

Page 18: ...reless asynchronous serial communication amongst two or more terminal devices There are three basic elements to any ENC 900 communications network One module configured as the Master Zero or more modules configured as Repeaters One or more modules configured as Remotes The function of the Master is to provide synchronization for the entire network and to control the flow of data There is always on...

Page 19: ...estriction to the number of Repeaters and Remotes that can be added to a network As seen in Network 4 a Master can communicate directly with both Remotes and Repeaters 3 2 Command Mode The ENC 900 firmware has been designed to allow the user to customize the operation of the modem through an AT Command Interface This interface is ideal for direct interface with another microcontroller or for highe...

Page 20: ... telephone modem command set All line entries must be preceded by the characters AT The characters AT are known as the attention characters and must be typed at the beginning of each command line For example to change the operating mode type ATS101 2 ENTER The modem should respond with OK The above command will set the operating mode to Master Point to Point Register settings are not immediately s...

Page 21: ...ata Mode the modem will communicate through the serial port at the same baud rate as was last used in Command Mode2 To return to Command Mode you can either Send the escape sequence The escape sequence consists of 1 second of inactivity followed by the characters followed by another second of inactivity or Toggle the DTR line depending on the D parameter The escape sequence must be issued at the b...

Page 22: ...e used to quickly configure the modem for a particular type of operation For example to quickly implement Network 1 Factory default 1 would be applied to the Master and Factory default 2 would be applied to the Remote To quickly set up Network 2 apply Factory 1 to the Master Factory 3 to the Repeater and Factory 4 to the Remote These defaults will get you started and only ensure that a link can be...

Page 23: ...dem As data is sent from Remote to Master the RX indicator should blink on as correct packets of data are received At this point the Master s RSSI LED s should become active It is recommended that if the ENC 900 will be deployed in the field where large distances separate the units the modems should be configured and tested in close proximity e g in the same room first to ensure a good link can be...

Page 24: ... return E Command Echo Your modem is preset to return or echo commands to the host microprocessor when in Command Mode E0 No Command Echo E1 Command Echo I Identification The I command returns various modem information settings I0 String up to 15 characters stored in non volatile memory I1 Product Code I2 Self Test Result I3 Product Identification Firmware Version I4 Firmware Date I5 Firmware Copy...

Page 25: ...1 timing is still valid D DTR Data Terminal Ready The D command controls what action the modem performs when the DTR input line is toggled The DTR input is controlled by the host microprocessor D0 DTR line is ignored D1 Not Supported D2 De assert DTR to force the modem into command mode from data mode DTR must be asserted before putting the modem back into data mode The modem is put back into data...

Page 26: ...k When enabled the modem looks for the stop bit If the stop bit is absent the byte is thrown out When enabled the modem also does a parity check Note that the data format number of data bits parity type and number of stop bits is defined by S register 110 E0 Disable Framing Error Check E1 Enable Framing Error Check W Write Configuration to Memory The W command stores the active configuration into ...

Page 27: ... to zero the modem will power up in command mode If this register is set to one the modem will power up in data mode S Register 2 Escape Code This register contains the ASCII value of the escape character The default value decimal 43 is equivalent to the ASCII character Values greater than 127 disable the escape feature and prevent you from returning to the Command Mode This register cannot be sto...

Page 28: ...on for data transmitted by all Remotes and Repeaters In addition the Master defines the following network parameters to be utilized by all other modems in the network See the appropriate sections for a complete description of these parameters Maximum Packet Size S112 Minimum Packet Size S111 Wireless Link Rate S103 Hop Interval S109 2 Master Point to Point This mode of operation provides for commu...

Page 29: ...S213 4 Repeater A more precise title would be Repeater Remote because a Repeater also has much of the same functionality as a Remote A terminal can be connected at the Repeater location and communicate with the Master terminal There is no restriction to the number of Repeaters in a network allowing for communication over virtually limitless distances The presence of one Repeater in a network autom...

Page 30: ...4400 7 9600 8 7200 9 4800 10 3600 11 2400 12 1200 It is generally advisable to choose the highest rate that your terminal equipment will handle to maximize performance unless a limitation on the available bandwidth is desired If the DTE is a personal computer the port can usually be used reliably at 115200 Issuing the Fx command factory default does not affect the current setting of S102 S Registe...

Page 31: ...ty of communications where multiple networks may operate concurrently in close proximity it is suggested that a typical value be chosen perhaps something meaningful yet not easily selected by chance or coincidence Default is 1 S Register 105 Unit Address In point to point operation the Unit Address on both the Master and Remote or Repeater units must be the same In a multipoint system the Unit Add...

Page 32: ...on below When communicating with the Master R1 is acting like a Remote on Primary Hopping Pattern 1 When communicating with R2 and S4 R1 is acting like a Master on Secondary Hopping Pattern 2 If multiple Repeaters are used they should have different Secondary Hopping Patterns R1 1 2 R2 2 5 S3 5 M 1 S4 2 R5 1 3 R6 3 6 S7 6 R8 1 4 S9 4 Note that all units have a unique Unit Address Networks of any c...

Page 33: ...n The allowable settings are 0 1 mW 1 10 mW 2 100 mW 3 1000 mW not available for ENC 900L model Ideally you should test the communications performance between units starting from a low power level and working upward until the RSSI is sufficiently high and a reliable link is established Although the conditions will vary widely between applications typical uses for some of the settings are described...

Page 34: ...6dBi 3 85dBd were to be used the power setting must be adjusted appropriately Violation of FCC regulations can result in severe fines S Register 109 Hopping Interval This option determines the frequency at which the modems change channel Note that the Master controls this parameter for the entire network This setting is ignored in units configured as Remotes or Repeaters The allowable settings are...

Page 35: ...er and abide by the Master s S111 setting If S114 1 at any particular Repeater or Remote that Repeater or Remote will use its own local S111 setting The default for S111 is 1 byte S Register 112 Maximum Size This setting has a range of 2 to 255 and defines the maximum number of bytes from the DTE which should be encapsulated in a packet This value should be greater than the minimum packet size but...

Page 36: ...communicating In this case the Master will continue to retransmit until an acknowledgement is received or the retransmission limit is reached When the retransmission limit is reached the Master discards the packet The Master retransmits once at the beginning of each hopping interval until the limit is reached This parameter is not necessary in Remote units since all Remotes receive acknowledgement...

Page 37: ...ntervals for less frequent transmission or to avoid collisions between many Remotes in the system This register is always disregarded and taken as S115 1 in Point to Point mode S Register 117 Radio Buffer Mode Radio Buffer Mode controls the ENC 900 TX buffer behaviors The allowable settings for this register are 0 High Throughput Mode 1 Quick Turn Around Mode S Register 118 Roaming This mode is ac...

Page 38: ...CD Framing S Register 121 DCD Timeout The ENC 900 supports two special types of data framing Input or RTS CTS Data Framing and Output or DCD Data Framing Input Data Framing is enabled by configuring the Handshaking Parameter as K2 This type of framing makes use of the S120 parameter as illustrated in Figure 9 Parameter S120 can be set to any value between 0 and 254 ms RTS CTS TXD S120 ms Data goin...

Page 39: ... Retry Limit Packet Retry Limit is analogous to Packet Retransmissions but specifically applies to Remotes and Repeaters This parameter is not used by the Master Because the Remote has the advantage of receiving acknowledgements from the Master it is not necessary to blindly retransmit each packet If the Remote does not get an acknowledgement on the next hop it will retransmit its packet This will...

Page 40: ...This feature also displays average received signal strength for 12 channels above the 902 928 MHz ISM band This area of the spectrum is used by paging networks When deploying a network the spectrum analyzer feature is useful for determining which parts of the ISM band may be noisy This knowledge can be used to select an appropriate hopping pattern or for creating a custom hopping pattern which avo...

Page 41: ...ify Table 4 provides a diagnostics command summary The first column is a list of commands that may be issued at the master The second column is the corresponding remote register In general any command issued without any additional parameters is a read command For example if you type 0 return The remote Remote repeater will send back the value if its S101 register On the Master terminal screen you ...

Page 42: ...back a test string from remote b x E Framing c x C DCD d x K Handshaking e W Write f S123 RSSI g x S104 Network Address h x S106 Hopping Pattern I x S206 Secondary Hopping Pattern j x S113 Retransmissions k1 statistics Read of data packets sent k2 statistics Read of data packets received k3 statistics Read of Remote s retries k4 statistics Read of Remote s packets dropped k5 statistics Read of Rem...

Page 43: ... can quickly interrogate modify many different Remote s settings without the delays associated with switching between command and data modes The commands which apply to the master s own registers are shown in Table 5 Table 5 Master Diagnostics Commands Command Master Register Description n x Remote Hop loading p Remote IO string read r x S105 Unit Address s S101 back to normal operating mode t x S...

Page 44: ...40 ENC 900 Operating Manual Chapter 4 Configuration ...

Page 45: ...n in data off in command mode V View Configuration W Write configuration to memory Sxx Read S register value Sxx yy Set S register value Result Codes 0 OK 3 NO CARRIER 4 ERROR S Registers S0 Auto Answer 0 255 0 power up in Command Mode non zero power up in Data Mode S2 Escape code 0 255 default S101 Operating Mode 1 Master Point to Multipoint 2 Reserved 3 Remote 4 Repeater S102 Serial Baud Rate 1 ...

Page 46: ...42 ENC 900 Operating Manual Appendix A Modem Command Summary ...

Page 47: ...8 0 Quick Enter to Command S119 0 RTS DCD Framing ms S120 5 DCD Timeout ms S121 0 Secondary Hop Pattern S206 2 Packet Retry Limit S213 0 AT F3 Repeater Default Settings E1 Q0 V1 W0 S0 1 S2 43 S3 13 S4 10 S5 8 DCD C2 DTR D0 Framing E0 Handshaking K0 DSR S1 Operating Mode S101 4 Serial Baud Rate S102 5 Wireless Link Rate S103 2 Network Address S104 1 Unit Address S105 3 Primary Hop Pattern S106 0 En...

Page 48: ...44 ENC 900 Operating Manual Appendix B Factory Default Settings ...

Page 49: ...r Consumption 900 mA at 1W transmit 28 mA receive and less than 1mA in sleep Operating Frequency 902 928 MHz Sensitivity 103 dBm Output Power 1 10 100 1000mW user selectable Spreading Code Frequency Hopping Hopping Patterns 64 pseudo random user selectable Error Detection CRC 16 with auto re transmit Error Correction User selectable Forward Error Correction FEC Adjacent Channel Rejection 40 dB Out...

Page 50: ...46 ENC 900 Operating Manual Appendix C Technical Specifications ...

Page 51: ...erformed by using a polynomial algorithm on data and appending a checksum to the end of the packet At the receiving end a similar algorithm is performed and checked against the transmitted checksum Crossover cable Also known as rollover null modem or modem eliminator cable A cable which allows direct DTE to DTE connection without intermediate DCEs typically used to bridge the two communicating dev...

Page 52: ...more accurately RS 232C or EIA TIA 232E Defined by the EIA a widely known standard electrical and physical interface for linking DCEs and DTEs for serial data communications Traditionally specifies a 25 pin D sub connector although many newer devices use a compact 9 pin connector with only the essential signaling lines used in asynchronous serial communications Lines have two possible states high ...

Page 53: ...ressly approved by Encom Wireless Data Solutions Inc could void the user s authority to operate the equipment This device has been tested with MCX and Reverse Polarity TNC connectors with the antennas listed in Appendix A Maximum allowed TX power on the radio will be factory reduced if antenna gain higher than 6 dBi is ordered An ordered antenna will be shipped with the radio module if a buyer has...

Page 54: ...50 ENC 900 Operating Manual Appendix E Approved Antennas ...