User`s guide

Copyright © 2012 congatec AG TCEDm10 64/94
7.5 Boot Strap Signals
Table 28 Boot Strap Signal Descriptions
Signal Pin # Description of Boot Strap Signal I/O PU/PD Comment
AC/HDA_SYNC A29 High Denition Audio Sync: This signal is a 48 kHz xed rate sample
sync to the codec(s). It is also used to encode the stream number.
O 3.3VSB AC/HDA_SYNC is a boot strap signal
(see caution statement below)
AC/HDA_SDOUT A33 High Denition 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 Mb/s for High Denition Audio.
O 3.3VSB AC/HDA_SDOUT is a boot strap signal
(see caution statement below)
LVDS_I2C_DAT A84 DDC lines used for at panel detection and control. I/O 3.3V PU 2k2
3.3V
LVDS_I2C_DAT is a boot strap signal
(see caution statement below).
SPKR B32 Output for audio enunciator, the “speaker” in PC-AT systems O 3.3V PD 1k SPKR is a boot strap signal (see caution
statement below)
EXCD0_PERST# A48 ExpressCard 0 Reset O 3.3V PD 2.2k EXCD0_PERST# is a boot strap signal
DDI1_CTRLDATA_AUX-
DP1_AUX-
HDMI_CTRLDATA
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.
I/O PCIE
I/O OD 3.3V
PU100k
3.3V
DDI1_CTRLDATA_AUX- is a boot strap
signal (see caution statement below).
DDI2_CTRLDATA_AUX-
DP2_AUX-
HDM2_CTRLDATA
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 PCIE
I/O OD 3.3V
PU100k
3.3V
DDI2_CTRLDATA_AUX- is a boot strap
signal (see caution statement below).
LPC_CLK B10 LPC clock output - 33MHz nominal O 3.3V PD 10k LPC_CLK is a bootstrap signal (see
caution statement below)
Caution
The signals listed in the table above are used as chipset conguration 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 conguration 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.