Specifications

Cinterion
®
ALAS5V Hardware Interface Description
2.1 Application Interface
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 ALAS5V_HID_v00.030a 2019-03-20
Confidential / Preliminary
Page 31 of 124
2.1.4 Serial Interface ASC0
ALAS5V offers an 8-wire (plus GND) unbalanced, asynchronous modem interface ASC0 con-
forming to ITU-T V.24 protocol DCE signaling. 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). For electrical characteristics please refer to Table 4.
ALAS5V 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 6: Serial interface ASC0
Features:
• Includes the data lines TXD0 and RXD0, the status lines RTS0 and CTS0, and 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 115,200 to 921,600bps.
• Supports RTS0/CTS0 hardware flow control.
Note: If the ASC0 serial interface is the application’s only interface, it is suggested to connect
test points on the USB signal lines as a potential tracing possibility.