EMAC SoM-250ES User manual

SoM-250ES
SoM 200-pin Carrier Board
User Manual
REV. 1.4
Copyright 2014
EMAC, Inc.

Table of Contents
Disclaimer.................................................................................................................................................. 1
1SoM-250 Product Summary.............................................................................................................. 2
1.1 Specifications...............................................................................................................................................................3
2SoM-250 Product Details................................................................................................................... 4
2.1 Jumper Configuration & Connector Descriptions........................................................................................................4
2.2 Power Connectors........................................................................................................................................................5
2.3 Ethernet........................................................................................................................................................................5
2.4 CAN Port .....................................................................................................................................................................5
2.5 Serial Ports...................................................................................................................................................................5
2.5 USB Host Ports............................................................................................................................................................7
2.6 Audio Port....................................................................................................................................................................7
2.7 LCD Brightness Control ..............................................................................................................................................7
2.8 MicroSD Card Socket.................................................................................................................................................7
2.9 Keyboard/Mouse..........................................................................................................................................................7
2.10 Analog Inputs...............................................................................................................................................................7
2.11 I/O Expansion ..............................................................................................................................................................8
2.12 Real-Time Clock..........................................................................................................................................................8
2.13 Reset ............................................................................................................................................................................8
3Software............................................................................................................................................... 9
3.1 Introduction..................................................................................................................................................................9
4Appendix A: Connector Pinouts...................................................................................................... 10
4.1 Ethernet 10/100 Base-T connector (JK2)...................................................................................................................10
4.2 USB Connector (JK3, JK4, HDR5) ...........................................................................................................................10
4.2.1 PortA (JK3 - Host)............................................................................................................................................10
4.2.2 PortC (JK4 –OTG)............................................................................................................................................10
4.2.3 PortA/B (HDR5)................................................................................................................................................10
4.3 Power Jack (JK1).......................................................................................................................................................10
4.4 Power Connector (J1) ................................................................................................................................................10
4.5 MicroSD Socket (SOK1)...........................................................................................................................................11
4.6 CAN (CN5)................................................................................................................................................................11
4.7 TTL LCD/Touch/Backlight (CN6)............................................................................................................................11
4.8 LVDS LCD/Touch/Backlight (HDR6) ......................................................................................................................12
4.9 Misc. General Purpose I/O (HDR1)...........................................................................................................................12
4.10 COMA RS-232 Serial Port (CN2) ............................................................................................................................13
4.11 COMB RS-232 Serial Port (HDR3)..........................................................................................................................13
4.12 COMC RS-232/422/485 Serial Port (HDR4) ...........................................................................................................13
4.13 COMD RS-232 Serial Port (HDR2) .........................................................................................................................13
4.14 PCD Expansion Connector (ABJ1)............................................................................................................................14
4.15 Touch Screen Connector (CN1).................................................................................................................................14
4.16 Touch Screen Connector (CN3).................................................................................................................................14
4.17 LCD Backlight Connector (CN4) ..............................................................................................................................14
5Appendix B: Jumper Settings .......................................................................................................... 15
6Appendix C: Mechanical drawing with dimensions....................................................................... 16

SoM-250ES_User_Manual_v1.40.doc -1- Rev 1.4 © 2014 EMAC, Inc.
Disclaimer
EMAC Inc. does not assume any liability arising out of the application or use of any of its products or designs.
Products designed or distributed by EMAC Inc. are not intended for, or authorized to be used in, applications such
as life support systems or for any other use in which the failure of the product could potentially result in personal
injury, death or property damage.
If EMAC Inc. products are used in any of the aforementioned unintended or unauthorized applications, Purchaser
shall indemnify and hold EMAC Inc. and its employees and officers harmless against all claims, costs, damages,
expenses, and attorney fees that may directly or indirectly arise out of any claim of personal injury, death or
property damage associated with such unintended or unauthorized use, even if it is alleged that EMAC Inc. was
negligent in the design or manufacture of the product.
EMAC Inc. reserves the right to make changes to any products with the intent to improve overall quality, without
further notification.

SoM-250ES_User_Manual_v1.40.doc -2- Rev 1.4 © 2014 EMAC, Inc.
1SoM-250 Product Summary
Features
•200 Pin SODIMM SoM Connector
•Inexpensive Open-Frame Design
•10/100BaseT Ethernet
•3 RS232 & 1 RS232/422/485 Port
•2 USB 2.0 (High Speed) Host port
•1 USB 2.0 (High Speed) OTG port
•1 CAN 2.0B port
•Socketed Battery
•1 SD/MMC Flash Card Sockets
•1 I2S Audio CODEC with Line-In/Line-Out
•1 Audio Beeper
•Operating Voltage of 12 to 26 Vdc.
•800 x 480 (WVGA) or 1024 x 600 (WSVGA) LCD with LED Backlight
•Touchscreen Interface and Software Controlled Backlight On/Off & Brightness
•FREE Qt Creator IDE with GCC & GDB development tools

SoM-250ES_User_Manual_v1.40.doc -3- Rev 1.4 © 2014 EMAC, Inc.
1.1 Specifications
LCD –7” LCD (SoM-250ES-000)
•Display Type: 7" TFT Color LCD
•Resolution: 800 x 480 WVGA @ 256K Colors
•Dot pitch: 0.19mm x 0.19mm
•Luminance: 330 (cd/m²)
•Viewing Angle: 55°
•Brightness: Software controlled
•Backlight: White LED (33 LEDS)
•Light Transparency: 80%
•Durability: Over one million touches
LCD –10” LCD (SoM-250ES-001)
•Display Type: 10" TFT Color LCD
•Resolution: 1024 x 600 WSVGA @ 256K Colors
•Dot pitch: 0.22mm x 0.22mm
•Luminance: 250 (cd/m²)
•Viewing Angle from Center: From top, 40° min. (50° typ.), From bottom, 50° min. (60° typ.),
Left and Right, 60° min. (70° typ.)
•Brightness: Software controlled
•Backlight: White LED
•Durability: Over one million touches
Touchscreen Controller
•Type: 4 Wire Analog Resistive
•Resolution: Continuous
•Controller: Built-In
•Driver: WinCE, Linux
Ethernet interface
•Ethernet Type: 10/100 Base-T Ethernet
•Ethernet Interface: On-Board RJ-45 connector
Solid-state Flash Disk
•Removable: 8+ GB of SD, MMC, or SDHC Flash Disk
Mechanical and Environmental
•Dimensions: 7.55" L x 4.15" W x 1.5" H
•Weight: 1.06 lbs..
•Power Supply Voltage: +12 to +26 Vdc.
•Power Consumption: typical ~200 ma. @ 24 Vdc.
•Operating Temperature: 0 ~ 60° C (32 ~ 140° F)
Standard Parts Inventory
•SoM-250 Assembly with 7.0” Touchscreen LCD
•Stainless Steel Mounting Bracket
•Three Serial Port cables
•CDROM with manuals, schematics, and drivers

SoM-250ES_User_Manual_v1.40.doc -4- Rev 1.4 © 2014 EMAC, Inc.
2SoM-250 Product Details
2.1 Jumper Configuration & Connector Descriptions
The SoM-250 comes factory configured. In the event that jumpers need to be verified or modified this section
provides the information required, including instructions on setting jumpers and connecting peripherals, switches
and indicators. Be sure to read all the safety precautions before you begin any configuration procedure. See
Appendix A for connector pinouts and Appendix B for Jumper Settings.
Table 1: Jumpers (see SoM manual for correct Boot settings)
Label
Function
Default
JB1
Boot0 Source Selection
Position B
JB2
Boot1 Source Selection
Position A
JB3
Resident Flash Write Protect
Position B
JB4
RTC Battery ON/OFF
Off
JB5
Serial Port RS422/485 Tx Enable
422
JB6
Serial Port RS232 or 422/485 Mode
232
Table 2: Connectors
Label
Function
CN1
7” Touch Screen Connector
CN2
Serial Port COM A
CN3
10” Touch Screen Connector
CN4
7” LCD Backlight Connector
CN5
CAN Port
CN6
7” LCD Data Connector
J1
Vin Locking Connector
JK1
Vin Power Barrel Jack
JK2
Ethernet
JK3
USB Host Port A & B
JK4
USB OTG Port C
JK5
Audio Input Jack
JK6
Audio Output Jack
HDR1
Misc. I/O Connector
HDR2
Serial Port COM D
HDR3
Serial Port COM B
HDR4
Serial Port COM C
HDR5
Bulkhead USB Connector Port A & B
HDR6
LVDS & Touch Signal Connector
SOK1
MicroSD Card Socket
SOK2
200 pin SOM Socket
ABJ1
PCD-E12 Expansion Module Connector

SoM-250ES_User_Manual_v1.40.doc -5- Rev 1.4 © 2014 EMAC, Inc.
2.2 Power Connectors
The SoM-250 provides two power connectors. J1 is an AMP/Tyco locking power connector (part# 640445-3),
three-pin type connector that mates with TE Connectivity part# 3-640600-3 power connector. Using this power
input provides for a more rugged/industrial locking connection. JK1 is a standard 5.5mm barrel jack with an inner
diameter of 2.1mm with a center V+ connection. This jack allows for easy connection to a wall mount power
supply (EMAC part number PER-PWR-00035). The SOM-250’s power input uses a switching regulator and allows
a voltage input of +12V DC to +26V DC.
The pinout for the J1 power connector is as follows:
Pin Signal
1 +Vin (+12Vdc to 26Vdc)
2 Chassis GND
3 System GND
2.3 Ethernet
The SoM-250 provides 10/100 Base-T full duplex Ethernet and uses a standard RJ-45 connector (JK2). It can be
connected straight to a hub, or another computer via a crossover Ethernet cable. The Ethernet MAC & PHY are
integrated into the SoM processor module. Activity and Link LEDs are integrated into the RJ45 connector.
2.4 CAN Port
The SoM-250 includes a CAN 2.0B port utilizing the TI SN65HVD232 CAN Transceiver chip. Note the CAN
controller must be supported by the SOM in order to have CAN functionality.
The pinout for the CN5 power connector is as follows:
Pin Signal
1 CAN_H
2 CAN_L
3 GND
2.5 Serial Ports
The SoM-250 is equipped with four serial ports, one of which terminates to a male DB9 and the other three which
terminate to 10pin header connectors (see table 2, 3, & 4 below). Three 10-pin header to male DB9 connector
cables are provided, giving easy access to these ports. Baud Rate, stop bits, etc. are all programmable for each
port via software.
COM A is an RS232 compatible port with a full complement of handshaking lines allowing it to communicate with
modems and other devices requiring hardware flow control.
COM B is an RS232 port. This port offers no handshake lines.
COM C can be configured to RS232, RS422, and RS485 via 2 jumpers. To select RS232 set jumper JB6 to 232
(this is the default). For RS422 set jumper JB6 to 4xx and jumper JB5 to 485. To select RS485, set jumper JB6 to
4xx and jumper JB5 to 422.
When using COM C in the RS422/485 mode, a terminating resistor (~120 Ohm) is recommended on the two far
ends of the network.
COM D is an RS232 port. This port offers no handshake lines.

SoM-250ES_User_Manual_v1.40.doc -6- Rev 1.4 © 2014 EMAC, Inc.
Table 1 (COM A Pinout)
#
Pin Description for DB9
Connector
1
DCD
2
RxD
3
TxD
4
DTR
5
GND
6
DSR
7
RTS
8
CTS
9
RI
10
Shield
Table 2 (COM B Pinout)
#
Pin Description for 10-
Pin Header
Pin Description for DB9
Connector
1
NC
NC
2
NC
RxD
3
RxD
TxD
4
NC
NC
5
TxD
GND
6
NC
NC
7
NC
NC
8
NC
NC
9
GND
NC
10
NC
-
Table 3 (COM C Pinout)
#
Pin Description for 10-Pin
Header
Pin Description for DB9
Connector
1
422/485 TX-
422/485 TX-
2
NC
232 RX, 422/485 TX+
3
232 RX, 422/485 TX+
232 TX, 422/485 RX+
4
RTS
422/485 RX-
5
232 TX, 422/485 RX+
GND
6
CTS
NC
7
422/485 RX-
RTS
8
NC
CTS
9
GND
NC
10
NC
-
Table 4 (COM D Pinout)
#
Pin Description for 10-
Pin Header
Pin Description for DB9
Connector
1
NC
NC
2
NC
RxD
3
RxD
TxD
4
NC
NC
5
TxD
GND
6
NC
NC
7
NC
NC
8
NC
NC
9
GND
NC
10
NC
-

SoM-250ES_User_Manual_v1.40.doc -7- Rev 1.4 © 2014 EMAC, Inc.
2.5 USB Host Ports
The SoM-250 provides one dual USB 2.0 (USB Port A & B) high speed host port (JK3). USB PortA and PortB
can be accessed from the bulkhead connector (HDR5). EMAC can provide a cable (CAB-40-004) to access these
ports.
In addition to the one USB Host port, the SoM-250 provides a USB On-The-Go (OTG) port. This port can be used
as either a USB Host or USB Device port.
All of the USB ports are equipped with 500mA re-settable Polyfuses. If a USB Device tries to draw more than
500mA from the port, the fuse will open until the device is unplugged or its current requirement is reduced. There
is no software provision for shutting down power to the Ports or detecting when a port is drawing too much
current.
Note: When sizing a power supply, make sure to allow for USB Device consumption. A device can potentially
draw 500mA, therefore these devices could use a total of up to 1 amp of power.
2.6 Audio Port
The SoM-250 provides Audio Line Out and Line In capability through two standard audio jacks (JK5 & JK6). Audio
Jack JK5 is stereo line level input and Audio Jack JK6 is stereo line level output. The processor interfaces to the
Audio CODEC through its I2S interface. Command control of the CODEC is done using the processor’s SPI
interface. The CODEC is the Cirrus CS4271, which is a high performance 24-bit Stereo CODEC offering superior
sound quality.
Both the input and output are line level. You will probably not be able to drive an unamplified speaker although
standard headphones will work. Likewise, an un-amplified microphone probably will not work as an input although
the line out of a CD player will work.
2.7 LCD Brightness Control
The SoM-250 offers LCD brightness control that can change the brightness of the LCD via software. The LCD
utilizes LED backlighting. The board provides the backlight with approximately 10 volts at about 220mA. The
processor provides a PWM (SoM pin# 85) that is used to drive the LCD backlight. Changing the duty-cycle of the
PWM directly affects the brightness of the LCD. In addition, the backlight can be turned off or on via SoM port line
GPIO0 (SoM pin#114). This allows screensaver software to automatically turn off the backlight when the unit is
not being used and to automatically turn it back on when the touchscreen is touched.
2.8 MicroSD Card Socket
The SoM-250 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 LD3) 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 SoM-250 can be read by another computer using an MicroSD card reader. The MicroSD
interface is compatible with Standard and High Capacity MicroSD cards.
2.9 Keyboard/Mouse
The SoM-250 does not provide a PS/2 type keyboard/mouse interface. However, a USB keyboard and mouse
can be used if required.
2.10 Analog Inputs
The analog inputs are available on HDR1 (see table 5 below) and are labeled as analog_04, analog_05,
analog_06 and analog_07. These may or may not be supported by the SoM plugged into this carrier.

SoM-250ES_User_Manual_v1.40.doc -8- Rev 1.4 © 2014 EMAC, Inc.
2.11 I/O Expansion
The Processor used by the SoM-250 provides a number of unused I/O lines. The SoM-250 provides access to
these lines on connector HDR1. This 44-pin dual row header contains GPIO lines, SPI bus, I2C 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.
Pin
Signal
Pin
Signal
1
3.3V
2
3.3V
3
GPIO1
4
GPIO4
5
GPIO2
6
GPIO5
7
GPIO3
8
GPIO6
9
INT0
10
GPIO7
11
INT1
12
GND
13
OSC0
14
GND
15
OSC1
16
GND
17
ADC4
18
GND
19
ADC5
20
GND
21
ADC6
22
GND
23
ADC7
24
GND
25
SPI_MISO
26
GND
27
SPI_MOSI
28
GND
29
31
33
35
37
39
41
43
SPI_CLK
SPI_CS3
SPI_CS1
I2C_DAT
I2C_CLK
*SOM_RSTOUT
5V_VCC
GND
30
32
34
36
38
40
42
44
GND
GND
GND
GND
GND
GND
5V_VCC
GND
2.12 Real-Time Clock
The SoM-250 is equipped with an external battery for backing up the module’s Real-Time Clock (RTC). Drivers to
access the RTC are included in the operating systems. Jumper JB4 should be placed in the ON position in order
to retain system time when powered down.
2.13 Reset
The SoM-250 provides a Reset Button (PB1). Pressing this button will cause the system to reset.

SoM-250ES_User_Manual_v1.40.doc -9- Rev 1.4 © 2014 EMAC, Inc.
3Software
3.1 Introduction
Whatever module is used in the SoM-250 can be programmed in a variety of languages and utilize a variety of
Operating Systems. There are a number of Free compilers, interpreters, and assemblers available allowing the
processor module to be programmed in C, BASIC or Assembly languages. EMAC has Board Support Package
available for Linux. For more information on these particular Operating Systems, contact EMAC, Inc.
For more information on Software, see the module’s User’s Manual.
Note: All of the links in this document are subject to change. Please contact EMAC for updated link locations if
necessary.

SoM-250ES_User_Manual_v1.40.doc -10- Rev 1.4 © 2014 EMAC, Inc.
4Appendix A: Connector Pinouts
4.1 Ethernet 10/100 Base-T connector (JK2)
Pin Signal
1 XMT+
2 XMT-
3 RCV+
4 N/C
5 N/C
6 RCV-
7 N/C
8 N/C
4.2 USB Connector (JK3, JK4, HDR5)
4.2.1 PortA & B (JK3 - Host)
Pin Signal
1 USB_PWR (5V DC)
2 USB_Data-
3 USB_Data+
4 GND
4.2.2 PortC (JK4 –OTG)
Pin Signal
1 USB_VBUS
2 USB_Data-
3 USB_Data+
4 USB_ID
5 GND
4.2.3 PortA/B (HDR5)
Pin Signal Pin Signal
1 USB_PWR_A 2 USB_PWR_B
3 USB_HOSTA- 4 USB_HOSTB-
5 USB_HOSTA+ 6 USB_HOSTB+
7 GND 8 GND
9 Chassis GND 10 NC
4.3 Power Jack (JK1)
Pin Signal
Center 5V DC
Barrel GND
4.4 Power Connector (J1)
Pin Signal
1 Vin
2 Chassis GND
3 System GND

SoM-250ES_User_Manual_v1.40.doc -11- Rev 1.4 © 2014 EMAC, Inc.
4.5 MicroSD Socket (SOK1)
Pin Signal
1 DAT2
2 CD/DAT3
3 CMD
4 VCC (3.3V)
5 SCLK
6 GND
7 DAT0
8 DAT1
9 SD Card Detect
10 GND
4.6 CAN (CN5)
Pin Signal
1 CAN_H
2 CAN_L
3 GND
4.7 TTL LCD/Touch/Backlight (CN6)
Pin Signal
1 CLK
2 HSYNC
3 VSYNC
4 GND
5 R0
6 R1
7 R2
8 R3
9 R4
10 R5
11 GND
12 G0
13 G1
14 G2
15 G3
16 G4
17 G5
18 GND
19 B0
20 B1
21 B2
22 B3
23 B4
24 B5
25 GND
26 DEN
27 VCC
28 VCC
29 R/L
30 U/D

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4.8 LVDS LCD/Touch/Backlight (HDR6)
Pin Signal Pin Signal
1 GND 2 GND
3 3.3V 4 3.3V
5 RED - 6 RED +
7 GND 8 GND
9 GREEN - 10 GREEN +
11 GND 12 GND
13 BLUE - 14 BLUE +
15 GND 16 GND
17 CLOCK - 18 CLOCK +
19 VLED +5V 20 VLED +5V
21 BRIGHTNESS 22 GND
23 EDID DATA 24 EDID CLOCK
25 3.3V 26 VLED +5V
27 Y2 28 X2
29 Y1 30 X1
31 GND 32 GND
33 VIN 34 VIN
4.9 Misc. General Purpose I/O (HDR1)
Pin Signal Pin Signal
1
3
3.3V
GPIO1
2
4
3.3V
GPIO4
5
GPIO2
6
GPIO5
7
GPIO3
8
GPIO6
9
INT0
10
GPIO7
11
INT1
12
GND
13
OSC0
14
GND
15
OSC1
16
GND
17
ADC4
18
GND
19
ADC5
20
GND
21
ADC6
22
GND
23
ADC7
24
GND
25
SPI_MISO
26
GND
27
SPI_MOSI
28
GND
29
31
33
35
37
39
41
43
SPI_CLK
SPI_CS3
SPI_CS1
I2C_DAT
I2C_CLK
*SOM_RSTOUT
5V_VCC
GND
30
32
34
36
38
40
42
44
GND
GND
GND
GND
GND
GND
5V_VCC
GND

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4.10 COMA RS-232 Serial Port (CN2)
Pin DB9 Signal
1 DCD
2 RxD
3 TxD
4 DTR
5 GND
6 DSR
7 RTS
8 CTS
9 RI
4.11 COMB RS-232 Serial Port (HDR3)
Pin HD3 Signal DB9 Signal
1 NC NC
2 NC RxD
3 RxD TxD
4 NC NC
5 TxD GND
6 NC NC
7 NC NC
8 NC NC
9 GND NC
10 NC --
4.12 COMC RS-232/422/485 Serial Port (HDR4)
Pin HD4 Signal DB9 Signal
1 422/485 TX- 422/485 TX-
2 NC 232 RX, 422/485 TX+
3 232 RX, 422/485 TX+ 232 TX, 422/485 RX+
4 RTS 422/485 RX-
5 232 TX, 422/485 RX+ GND
6 CTS NC
7 422/485 RX- RTS
8 NC CTS
9 GND NC
10 NC -
4.13 COMD RS-232 Serial Port (HDR2)
Pin HD2 Signal DB9 Signal
1 NC NC
2 NC RxD
3 RxD TxD
4 NC NC
5 TxD GND
6 NC NC
7 NC NC
8 NC NC
9 GND NC
10 NC --

SoM-250ES_User_Manual_v1.40.doc -14- Rev 1.4 © 2014 EMAC, Inc.
4.14 PCD Expansion Connector (ABJ1)
Pin Signal Pin Signal
1 VIN 2 RESET OUT
3 GND 4 SPI_MOSI
5 INT2 (5V) 6 SPI_MISO (5V)
7 SPI_CS0 8 SPI_CLK
9 5V 10 GPIO15
4.15 Touch Screen Connector (CN1)
Pin Signal
1 Y+
2 X+
3 Y-
4 X-
4.16 Touch Screen Connector (CN3)
Pin Signal
1 Y+
2 X+
3 Y-
4 X-
4.17 LCD Backlight Connector (CN4)
Pin Signal
1 VOUT (+)
2 SWITCHED GND (-)

SoM-250ES_User_Manual_v1.40.doc -15- Rev 1.4 © 2014 EMAC, Inc.
5Appendix B: Jumper Settings
(See SoM manual for correct Boot jumper settings)
JB1 Boot0 Source Selection
Jumper Position Setting
Pins 2 & 3 A Line pulled LOW
Pins 1 & 2* B Line pulled HIGH
* Default setting
JB2 Boot1 Option Selection
Jumper Position Setting
Pins 2 & 3* A Line pulled LOW
Pins 1 & 2 B Line pulled HIGH
* Default Setting
JB3 Flash Write Protect
Jumper Position Setting
Pins 2 & 3 A Resident Flash Disable
Pins 1 & 2* B Resident Flash Enable
* Default setting
JB4 RTC Battery Enable
Jumper Position Setting
Pins 1 & 2 ON Enable Battery Backup
Pins 2 & 3* OFF Disable Battery Backup
* Default setting
JB5 RS485/RS422 Select
Jumper Position Setting
Pins 1 & 2 485 Select RS485
Pins 2 & 3* 422 Select RS422
* Default setting
JB6 RS232/RS4xx Select
Jumper Position Setting
Pins 1 & 2* 232 Select RS232
Pins 2 & 3 4xx Select either RS422 or RS485 depending on JB5
* Default setting

SoM-250ES_User_Manual_v1.40.doc -16- Rev 1.4 © 2014 EMAC, Inc.
6Appendix C: Mechanical drawing with dimensions