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3.2.4 BOOT Strap Signals
Configuration straps are signals that, during system reset, are set as inputs (independently by their behaviour during normal operations) in order to allow the proper
configuration of the processor / chipset. For this reason, on Q7-A29 are placed the pull-up or pull-down resistors that are necessary to configure the board
properly.
The customer must avoid to place, on the carrier board, pull-up or pull-down resistors on signals that are used as strap signal, since it could result in malfunctions
of Q7-A29 module.
The following signals are used as configuration straps by Q7-A29 at system reset.
LPC_FRAME#: pin 190 of golden card edge connector. This pin determines if the board must boot using the embedded SPI Flash (default) or using an external
LPC Firmware Hub. Signal at +3.3V_A voltage level with a 10kΩ pull-up resistor.
LPC_CLK: pin 189 of golden card edge connector. This pin enables or disables (default) the internal Watchdog for boot failure event. Signal at +3.3V_A voltage
level with a 2k2Ω pull-down resistor.
Q7-A29
Q7-A29 - Rev. First Edition: 1.0 - Last Edition: 1.0 - Author: S.B. - Reviewed by G.G. Copyright © 2016 SECO S.r.l.
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