S42/Central Software User Guide
1VV0301318 Rev. 3
– 2018-08-31
Reproduction forbidden without written authorization from Telit Communications S.p.A.- All Rights Reserved.
Page 43 of 66
6.4.2.
Drive from "interface down" to "interface up" State
To initiate the state change from "interface down" state to "interface up" state the initiator shall
assert the IUR-OUT# signal.
The acceptor confirms the IUR-IN# signal with asserting its IUC-OUT# signal which is
connected to the IUC-IN# signal of the initiator.
Once the acceptor detects the assert of the IUR-OUT# signal from the initiator, it can disable
MCU power saving mechanisms but shall ensure the UART is ready to receive data before it
confirms asserting its IUC-OUT# signal which is connected to the IUC-IN# signal of the
initiator.
Once the initiator detects the assert of the IUC-IN# signal of the acceptor, the in initiator can
send data to the acceptor.
UICP State
interface up
pending interface up
interface down
IUR-OUT#
IUC-IN#
RTS/CTS UART Hardware flowcontrol
UART-TXD
data
t2
asserted
de-asserted
de-asserted
asserted
