Seco Qseven Q7-974 User Manual page 41

Rel. 2.0 comliant module with the intel bay trail family system-on-chips

Table of Contents

3.2.3.12

LPC interface signals

According to Qseven

specifications rel. 2.0, on the golden edge finger connector there are 8 pins that are used for implementation of Low Pin Count (LPC) Bus

interface.

Warning: Although the Qseven

option is intended only for the manufacturers of the modules who are free to choose the option they deem more appropriate.

On the Q7-974 module, the aforementioned pins have been dedicated to the LPC bus; use of these pins for different implementations other than

LPC (i.e. as GPIOs) is therefore not possible.

The following signals are available:

LPC_AD[0÷3]: LPC address, command and data bus, bidirectional signal, +3.3V_S electrical level.

LPC_CLK: LPC Clock Output line, +3.3V_S electrical level. Since only a clock line is available, if it is necessary to connect more LPC devices on the carrier board,

then provide for a zero-delay clock buffer to connect all clock lines to the single clock output of Qseven

LPC_FRAME#: LPC Frame indicator, active low output line, +3.3V_S electrical level. This signal is used to signal the start of a new cycle of transmission, or the

termination of existing cycles due to abort or time-out condition.

SERIRQ: LPC Serialised IRQ request, bidirectional line, +3.3V_S electrical level. This signal is used only by peripherals requiring Interrupt support.

3.2.3.13

SPI interface signals

The Intel

Atom E38xx family of SOCs offer also one dedicated controller for Serial Peripheral Interface (SPI), which can be used for connection of EEPROMs and

Serial Flash devices. This interface does not support platform firmware (BIOS).

SPI interface supports master mode only can support speed up to 15Mbps.

Signals involved with SPI management are the following:

SPI_MOSI: SPI Master Out Slave In, Output from Qseven

SPI_MISO: SPI Master In Slave Out, Input to Qseven

SPI_CLK: SPI Clock Output to carrier board's SPI embedded devices. Electrical level +3.3V_S.

SPI_CS0#: SPI Chip select, active low output signal (+3.3V_S electrical level).

Q7-974