Boot Strap Signals; Table 36 Boot Strap Signal Descriptions - Congatec COM Express conga-TC175 User Manual

8.5

Boot Strap Signals

Table 36 Boot Strap Signal Descriptions
Signal
AC/HDA_SDOUT
SPKR
DDI1_CTRLDATA_AUX-
DP1_AUX-
HDMI_CTRLDATA
DDI2_CTRLDATA_AUX-
DP2_AUX-
HDM2_CTRLDATA
Caution
The signals listed in the table above are used as chipset configuration straps during system reset. In this condition (during reset), they are
inputs that are pulled to the correct state by either COM Express™ internally implemented resistors or chipset internally implemented
resistors that are located on the module. No external DC loads or external pull-up or pull-down resistors should change the configuration of
the signals listed in the above table.
External resistors may override the internal strap states and cause the COM Express™ module to malfunction and/or cause irreparable
damage to the module.
Copyright © 2017 congatec AG
Pin # Description of Boot Strap Signal
A33 High Definition Audio Serial Data Out: This signal is the serial TDM
data output to the codec(s). This serial output is double-pumped for
a bit rate of 48 Mbps for High Definition Audio.
B32 Output for audio enunciator, the "speaker" in PC-AT systems
D16 Multiplexed with DP1_AUX- and HDMI1_CTRLDATA.
DP AUX- function if DDI1_DDC_AUX_SEL is no connect.
HDMI/DVI I2C CTRLDATA if DDI1_DDC_AUX_SEL is pulled high.
C33 Multiplexed with DP2_AUX- and HDMI2_CTRLDATA.
DP AUX- function if DDI2_DDC_AUX_SEL is no connect.
HDMI/DVI I2C CTRLDATA if DDI2_DDC_AUX_SEL is pulled high.
I/O PU/PD Comment
O 3.3VSB PU 1K
3.3VSB
O 3.3V
PU100k
I/O PCIE 3.3V
I/O OD 3.3V
PU100k
I/O PCIE 3.3V
I/O OD 3.3V
TCKLm10
AC/HDA_SDOUT is a boot strap
signal (see caution statement below)
SPKR is a boot strap signal (see
caution statement below)
DDI1_CTRLDATA_AUX- is a boot
strap signal (see not below).
DDI2_CTRLDATA_AUX- is a boot
strap signal (see not below).
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