BGS3 Hardware Interface Description
3.10 Serial Interface ASC1
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BGS3_HD_v01.000d
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2010-03-26
Confidential / Released
3.10
Serial Interface ASC1
BGS3 offers a 4-wire unbalanced, asynchronous modem interface ASC1 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 2.9V (for high data bit or inactive
state). For electrical characteristics please refer to
.
BGS3 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 module’s TXD1 signal line
•
Port RXD @ application receives data from the module’s RXD1 signal line
Figure 14:
Serial interface ASC1
Features
•
Includes only the data lines TXD1 and RXD1 plus RTS1 and CTS1 for hardware hand-
shake.
•
On ASC1 no RING line is available. The indication of URCs on the second interface
depends on the settings made with the AT^SCFG command. For details refer to
•
Configured for 8 data bits, no parity and 1 or 2 stop bits.
•
ASC1 can be operated at fixed bit rates from 300 bps to 921600 bps. Autobauding is not
supported on ASC1.
•
Supports RTS1/CTS1 hardware flow control and XON/XOFF software flow control.
Table 16:
DCE-DTE wiring of ASC1
V.24 cir-
cuit
DCE
DTE
Line function
Signal direction
Line function
Signal direction
103
TXD1
Input
TXD
Output
104
RXD1
Output
RXD
Input
105
RTS1
Input
RTS
Output
106
CTS1
Output
CTS
Input
