User's Manual

Table Of Contents
Cinterion
®
ELS61-AUS Hardware Interface Description
2.1 Application Interface
52
ELS61-AUS_HID_v00.031 2016-06-03
Confidential / Preliminary
Page 26 of 102
The following figure shows the startup behavior of the asynchronous serial interface ASC0.
For pull-up and pull-down values see Table 10.
Figure 7: ASC0 startup behavior
Notes:
During startup the DTR0 signal is driven active low for 500µs. It is recommended to provide a
470
serial resistor for the DTR0 line to prevent shorts.
No data must be sent over the ASC0 interface before the interface is active and ready to re-
ceive data (see Section 3.2.1).
An external pull down to ground on the DCD0 line during the startup phase activates a special
mode for ELS61-AUS. In this special mode the AT command interface is not available and the
module may therefore no longer behave as expected.