User's Manual
HiLo3G-850 User Manual
04 March 2011 - Page 19 / 36
However this configuration does not allow the signaling signals like:
• RI signal used when programmed to indicate an incoming voice or data call or SMS incoming etc…
• DCD signal used to signal the DATA connections
• DSR signal used to signal the module UART interface is ON (need to pull high DSR with 470K ohm to external 3V,
shown as below)
• DTR signal used to prevent HiLo3G-850 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-850 -host
When using only RX/TX instead of the complete V24 link, the following schematic could be used.