Freescale Semiconductor MPC5748G EVB, Руководство пользователя

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AV Interface Connectors
MPC5748G EVB User Guide, User Guide, Rev. 0, 08/2015
Freescale Semiconductor, Inc. 23
The MCU FlexRay pins are powered from the VDD_HV_A domain, which is configured between 3.3V
and 5.0 V on the daughtercard using jumper J5. The FlexRay tranceivers I/O voltage pin is connected to
the PER_HVA net configured with jumper J24 on the main EVB. Care must be taken to ensure that the
MCU VDD_HV_A and PER_HVA supplies are the same when using the FlexRay transceiver.
6.7. SD Card Socket (P200)
The EVB supports a 4-bit SD interface (note that MPC5748G supports 8-bit SD data) which is routed to
a full sized SD card connector on the underside of the EVB. There is no user configuration required.
The SD socket has hardware card detection (routed to PA0) and write protection (routed to PH8) status
outputs which will be grounded when active.
The MCU SD card signals are all in the VDD_HV_A domain. The SD card specification is for an
interface voltage of between 2.7V and 3.6V so the SD card can only be used when VDD_HV_A is set to
3.3V (PER_HVA has no impact on the voltage on the SD card)
CAUTION
If VDD_HV_A is set to 5V, damage may be caused to an SD card if an
attempt is made to access it in software. If you need to leave the SD card
in the socket with VDD_HV_A set to 5V, ensure all the SD card pads are
left as high impedance
7. AV Interface Connectors
This section details the Audio / Video interface connectors on the EVB. Each of these connectors can be
used to add additional daughtercards (not supplied) to add functionality.
7.1. SAI Audio Connectors (P24, P25)
The EVB includes two 0.1” headers that can be used to interface to an SAI audio board (available
separately, please consult your Freescale representative). There is no EVB configuration required when
using these connectors other than to ensure the EVB is switched off prior to fitting or removing the
daughtercard.
The pinout of the connectors is shown below for reference and these connectors can also be used for
GPIO connectivity
Important:
The EVB daughtercards are supplied with a 40 MHz crystal which is a requirement for FlexRay in
order to generate the correct clock timing. If you have changed the default crystal on the daughtercard
and wish to use FlexRay, you must ensure a 40 MHz crystal is fitted.
The SD socket is
mounted on the
underside of the
board in the top left
corner
The SAI audio
connector is on the
bottom edge of the
EVB