PPC-E4+ User Manual.doc
-9-
Rev 1.4 © 2015 EMAC, Inc.
2.6
MicroSD Card Socket
The PPC-E4+ provides a high capacity MicroSD socket. This socket is hot-swappable and can accept a wide
variety of Flash Cards. A green activity light (LED LD2) is located towards the left side of the socket. When the
processor is accessing the Flash card, this LED will be lit and the card should not be removed at this time. A card
that is written to by the PPC-E4+, can be read by another computer, using a MicroSD card reader. The MicroSD
interface is compatible with Standard and High Capacity MicroSD cards.
2.7
Keyboard/Mouse
The PPC-E4+ does not provide a PS/2 type keyboard/mouse interface. However, a USB keyboard and mouse
can be used if required.
2.8
Analog Inputs
The analog inputs are available on HDR1 (see table 6 below) and are labeled as analog_04, analog_05,
analog_06 and analog_07. Voltages applied to the inputs must be in the range of 0V to 3.3V with reference to
ground. Different operating systems may provide access to the analog inputs differently or even not at all. See
the operating system documentation for details. Note: In some cases using the Analog Inputs can have adverse
effect on the touchscreen sensitivity.
2.9
I/O Expansion
The Processor used by the PPC-E4+ provides a number of unused I/O lines. The PPC-E4+ provides access to
these lines on connector HDR1. This 20-pin dual row header contains GPIO lines, SPI bus, I
2
C bus, A/D lines,
interrupts and power pins. Signal names listed in the table below are the SoM names as defined in the SoM 200
pin specification.
Table 8
Pin
Signal
Pin
Signal
1
GND
2
3.3V
3
I2DAT
4
I2CLK
5
~RESET_OUT
6
SPI_MISO
7
SPI_CLK
8
SPI_MOSI
9
SPI_CS1
10
SPI_CS0
11
SPI_CS3
12
GPIO07
13
ANALG_05
14
GPIO13
15
ANALG_06
16
IROA
17
ANALG_04
18
GPIO15
19
ANALG_07
20
GPIO12
2.10
Real-Time Clock
The PPC-E4+
emulates a real time clock using the AT91SAM9G45 / 9M10’s onboard real time timer. Battery
backup is provided from the carrier board using the VSTBY pin. The SoM-9G45 / 9M10 will retain the RTT value
register during reset and hence use it as a RTC. The RTC has the provision to set Alarms that can interrupt the
processor. For example the processor can be placed in sleep mode and then later awakened via the Alarm
function.
