User's Manual
Table Of Contents
- Contents
- Tables
- Figures
- 1 Introduction
- 2 Interface Characteristics
- 2.1 Application Interface
- 2.2 RF Antenna Interface
- 2.3 Sample Application
- 3 Operating Characteristics
- 4 Mechanical Dimensions, Mounting and Packaging
- 5 Regulatory and Type Approval Information
- 6 Document Information
- 7 Appendix
Cinterion
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ELS31-/ELS51-US Hardware Interface Overview
2.1 Application Interface
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ELS31-US_ELS51-US_HIO_v01.000a 2016-12-28
Confidential / Preliminary
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2.1.2 Serial Interface ASC0
ELS31-US/ELS51-US offers an 8-wire unbalanced, asynchronous modem interface ASC0
conforming to ITU-T V.24 protocol DCE signalling. The electrical characteristics do not comply
with ITU-T V.28. The significant levels are 0V (for low data bit or active state) and 1.8V (for high
data bit or inactive state).
ELS31-US/ELS51-US is designed for use as a DCE. Based on the conventions for DCE-DTE
connections it communicates with the customer application (DTE) using the following signals:
• Port TXD @ application sends data to the module’s TXD0 signal line
• Port RXD @ application receives data from the module’s RXD0 signal line
Figure 3: Serial interface ASC0
Features:
• Includes the data lines TXD0 and RXD0, the status lines RTS0 and CTS0 and, in addition,
the modem control lines DTR0, DSR0, DCD0 and RING0.
• Configured for 8 data bits, no parity and 1 stop bit.
• ASC0 can be operated at fixed bit rates from 4800bps up to 921600bps.
• Supports RTS0/CTS0 hardware flow control. Communication is possible by using only RXD
and TXD lines, if RTS0 is pulled low.
• Wake up from SLEEP mode by RTS0 activation.
The ASC0 interface is dedicated to signaling via AT commands (3GPP standard 27.007 + mod-
ule specific AT commands).