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Digi m10
Technical Overview
And
Reference
Date: 12 January 2012
90033936_C
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Copyright Notice Digi International has prepared this manual for the use of its employees, agents, and its customers. This manual contains proprietary information, which is protected by copyright. Preparing derivative works or providing instruction based on this manual without written permission from Digi International is prohibited. All information in this manual is accurate and reliable to the best of Digi International's knowledge. Digi International may make improvements and / or ch
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Document Revision History Version Description Date 1.00 Initial release of the user manual 23 Sep 2008 1.10 FAQ section added and minor changes made 30 Sep 2008 1.20 Technical review changes and minor additions 21 Oct 2008 1.30 Extract hardware information into separate manual 20 Aug 2009 Rev A Complete revision 12 Nov 2009 Rev B Table 3 in section 4.2 revised to display correct format 4 Nov 2010 Rev C Updated section 4.6 12 Jan 2012
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Digi m10 Technical Overview Table of Contents About This Manual......................................................................................................................... 6 Target Audience .......................................................................................................................... 6 Symbols Used in This Manual ..................................................................................................... 6 Reference Documents ............
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Digi m10 Technical Overview List of Tables Table 1: Message Acknowlegements ............................................................................................ 16 Table 2: Temperature Out of Bounds Packet ................................................................................ 18 Table 3: Temperature Query Packet ............................................................................................. 19 Table 4: Temperature Query Response Packet ..................
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Digi m10 Technical Overview About This Manual This manual provides a detailed technical overview on how the Orbcomm satellite network operates, available message types, specific Digi message extensions, and other related technical information. Target Audience The target audience for this document is comprised engineers and other individuals with a technical background. A typical reader is an engineer who is familiar with the general concept of wireless data communications. Symbols Us
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Digi m10 Technical Overview Reference Documents The following documents were used to create this user guide, and provide more information about the technologies and standards involved using the Digi m10 ORBCOMM Satellite Modem. Department of Defense Test Method Standard for Environmental Engineering Considerations and Laboratory Tests, MIL STD 810E European Telecommunications Standards Institute, EN 300 832 (A1 version 1.1.1), Electromagnetic Compatibility for Mobile Earth Stations
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Digi m10 Technical Overview 1. General Description This chapter provides an overview of the Digi m10 Satellite Modem and its features. 1.1 Background The ORBCOMM system is a two-way system that supports communication to and from mobile or fixed satellite modems, also called Subscriber Communicators (SCs). In most applications, a message or other data is first generated by an SC. From that source, the message is transmitted to the nearest ORBCOMM satellite. The satellite downlinks the m
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Digi m10 Technical Overview 1.2 Communication using a Digi m10 Satellite Modem Once an antenna is properly hooked up to the Digi m10 and it has a clear line of sight to the sky, the Digi m10 can start communicating with satellites as they move overhead. Availability of satellites is highly dependent on regional location and how busy a satellite currently is; that is, the availability of slots. Figure 1: SCO Report Transmission Cycle To transmit a message through the Digi m10 to th
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Digi m10 Technical Overview When receiving a message through the Digi m10, a user creates a message using an SMTP client and sends it to the ORBCOMM GCC using the appropriate e-mail address (typically serial#X1@orbcomm.net for North America or serial#X1@orbcomm2.net for the rest of the world). When the message is received by the GCC, the GCC transmits it through the GES to the satellite in orbit, which then transmits the message down to the Digi m10. Once the message is received by the
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Digi m10 Technical Overview v 1.20 2. Types of Communication Methods 2.1 Data Reports A Data Report is the basic service element the Digi m10 uses to transmit or receive a single packet containing 6 bytes or less of user-defined data. A Data Report can require an acknowledgment of successful delivery to the ORBCOMM Gateway, but this acknowledgment can be omitted to save space segment resources. A Data Report can only use speed dials to indicate where the message should be delivered.
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Digi m10 Technical Overview 3. Terms and definitions: 3.1 Gateway An ORBCOMM Gateway consists of a Gateway Control Center (GCC) and one or more Gateway Earth Station (GES) sites, as well as the network components that provide interfacility communications. The principal role of the ORBCOMM Gateway is to provide message processing and subscriber management for a defined service area. This role includes serving as the “home” for ORBCOMM system subscribers, as well as providing the inter
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Digi m10 Technical Overview 3.2 Gateway Earth Station (GES) The role of the Gateway Earth Station (GES) is to provide an RF communications link between the message switch and the satellite constellation. It consists of medium gain tracking antennas, RF and modem equipment, and communications hardware and software for sending and receiving data packets. The GES equipment and site are designed for unattended operation. The GES uses radome-enclosed, VHF full-motion antennas with approximat
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Digi m10 Technical Overview inaccessible by the satellite constellation. The stored messages are transmitted when an ORBCOMM Gateway comes into satellite-transmission range. This concept applies to both sending (SC-Originated) and receiving (SC-Terminated) from a satellite modem point of view. More documentation can be found on the kit installation CD. To learn more, navigate to C:\Program Files\Digi\Digi m10 JumpStart Kit\documents please refer to either ORBCOMM Serial Interface Spec
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Digi m10 Technical Overview 3.9 Speed Dial The ORBCOMM gateway maintains a list of up to eight speed dials, or originator/recipient addresses for each satellite modem. Typically, these speed dials contain the e-mail addresses of frequent recipients or originators of messages to and from the satellite modem. The use of speed dials results in a reduced number of bytes in a message. The speed dials can also be used with message blocking to restrict addresses that can send to the satellite
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Digi m10 Technical Overview Service Level Description 0 No Acknowledgment Acknowledgment is generated only if message fails 1 to reach the GCC. Acknowledgment is generated when message has 2 successfully reached (or failed to reach) the GCC. Acknowledgment is generated only if message fails 3 to reach recipient. Acknowledgment is generated when message has 4 successfully reached (or failed to reach) the recipient. Note that service levels 0 and 1 are only used for SC-originat
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Digi m10 Technical Overview 3.13 GES-to-Satellite Channels The RF links that connect an ORBCOMM Gateway GES to an ORBCOMM satellite use a single 57.6-kbps uplink and downlink channel that uses the TDMA protocol. This protocol permits simultaneous RF links between a single satellite and several GES installations within the satellite footprint. It also provides a virtually seamless hand-over of a satellite from GES to GES under the centralized control of the GMSS. 3.14 GES-to-GCC Channe
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Digi m10 Technical Overview 4. Digi Extended Packets In addition to the ORBCOMM serial commands defined in the ORBCOMM Serial Specification, the following Digi Extended Packets are available to the host controller: • Temperature Out of Bounds Packet • Temperature Query • Temperature Query Response • NVM Data Corruption Alert Packet • Code Upgrade Packet • RTS/CTS Control Packet The following sections provide details about these packets. 4.1 Temperature Out of Bounds Packet Table
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Digi m10 Technical Overview 4.2 Temperature Query The Temperature Query packet (see Table 3) is sent from the host controller to query the Digi m10 temperature. Table 3: Temperature Query Packet 0 0x85/0x86 Packet Header 1 0x19 Packet Type 2 Length0 Length of the packet 3 Length1 4 Retry_count/ Pkt Sequence Number 5 Fletch0 Fletcher Checksum 6 Fletch1 Digi International, Inc. © 2009 Page 19 of 26
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Digi m10 Technical Overview 4.3 Temperature Query Response The Temperature Query Response packet (see Table 4) is sent from the Digi m10 to the host controller, indicating the satellite modem’s temperature in degrees Celsius. Table 4: Temperature Query Response Packet 0 0x05/0x06 Packet Header 1 0x1A Packet Type 2 Length0 Length of the packet 3 Length1 4 Retry_count/ Pkt Sequence Number 5 Temp0 Temperature value in little endian format.(This is a 32 6 Temp1 bit floating poi
