User's Manual

PCS3_HD_v01.000-03
Confidential / Preliminary
Page 28 of 101
2013-10-21
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PCS3 Hardware Interface Description
3.3 Power-Up / Power-Down Scenarios
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3.3.4 Configuring the IGT Line for Use as ON/OFF Switch
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The IGT line can be configured for use in two different switching modes: You can set the IGT
line to switch on the module only, or to switch it on and off. The switching mode is determined
by the parameter "MEShutdown/OnIgnition" of the AT^SCFG command. This approach is use-
ful for application manufacturers who wish to have an ON/OFF switch installed on the host de-
vice.
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By factory default, the ON/OFF switch mode of IGT is disabled:
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at^scfg=meshutdown/onignition
^SCFG: "MEShutdown/OnIgnition","off"
OK
# Query the current status of IGT.
# IGT can be used only to switch on PCS3.
IGT works as described in Section 3.3.1.
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To configure IGT for use as ON/OFF switch:
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at^scfg=meshutdown/onignition
^SCFG: "MEShutdown/OnIgnition","on"
OK
# Enable the ON/OFF switch mode of IGT.
# IGT can be used to switch on and off PCS3.
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We strongly recommend taking great care before changing the switching mode of the IGT line.
To ensure that the IGT line works properly as ON/OFF switch it is of vital importance that the
following conditions are met.
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Switch-on condition: If the PCS3 is off, the IGT line must be asserted for at least 100ms before
being released.
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Switch-off condition: If the PCS3 is on, the IGT line must be asserted for at least 2.1s before
being released. The module switches off after the line is released. The
switch-off routine is identical with the procedure initiated by AT^SMSO, i.e.
the software performs an orderly shutdown as described in Section 3.3.3.
Before switching off the module wait at least 5 seconds after startup.
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Figure 6: Timing of IGT if used as ON/OFF switch