User's Manual

Note d‘étude / Technical document :
URD1– OTL 5696.1– 003 / 72361 Edition 02
HILO 3G Application Note
17 January 2011 - Page 21 / 38
• DTR signal used to prevent HiLo3G from entering into sleep mode or to switch between Data and AT commands or to
hang up a call or to wake up the module etc…
3.5.4 Partial V24 (RX-TX)—Connection HiLo3G -host
When using only RX/TX instead of the complete V24 link, the following schematic could be used.
Figure 21: Partial V24 connection (2 wires) between HiLo3G and host
As DSR is active (low electrical level) once HiLo3G is switched on, DTR is also active (low electrical level), therefore
Vcc_3V
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