AXEL Lite SOM/AXEL Lite Evaluation Kit/pdf

Getting started

Kit Identification Codes

The development kits (DESK, XELK, XUELK, BELK, etc.) are identified by a couple of codes:

1. P/N Part Number identification code
2. S/N Serial Number identification code

These codes are printed on a label sticked to the box containing the kit.

For example, the following picture shows such a label of an Axel Ultra XELK (XELK-H-S) with Serial Number 0CFA

Label of Axel Ultra XELK (XELK-H-S)

These codes are required to complete the registration process of the kit.

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Unboxing

Once you've received the kit, please open the box and check the kit contents with the packing list included in the box, using the table on this chapter as a reference.

The hardware components (SOM, carrier boards and display) are pre-assembled, as shown in the picture below:

Kit Contents

The following table list the kit components:

Component	Description
	SBCX with AXEL Lite SOM
	Ampire AM-800480SETMQW 7” 800x480 LCD display LVDS interface
	DWS WiFi module
	AC/DC Single Output Wall Mount adapter Output: +12V – 2.0 A
	DB9 Male Serial port adapter
	MicroSDHC card with SD adapter

Order codes

Order code	Description
SBCX562012C2R-00	This code refers to the default configuration detailed above

microSD Layout

The microSD provided with is used to store:

• a bootable partition (mmcblk0p1, vfat) containing:
  • binary images (u-boot and kernel images)
  • documentation
  • DVDK virtual machine image
• root file system partition (mmcblk0p2, ext3)

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Connections

This section describes how to quick start the Evaluation Kit. The picture below shows the AXEL Lite SOM inserted into the Evaluation Kit:

The system is programmed to automatically boot Linux at power up, loading the bootloader, the kernel and device tree image and the root file system from the SD card memory.

To connect to the system:

• connect the 12Vcc power supply to JP2 on the board
• connect the DB9 adapter bracket to the J22 connector on the SBCX and connect the DB9 connector to the PC COM port through a NULL-modem cable (not provided)
  • start your favorite terminal emulator software on PC (eg: PuTTY, Minicom, ...); communication parameters are 115200,N,8,1
• (optional) connect the ethernet cable from your LAN hub/switch to the J16 RJ45 connector
  • start SSH, using the following parameters:
    • ip address: depends on eth0 configuration made via serial console or systemd services, see How_to_configure_the_network_interfaces
    • username: root
    • password: empty field

First boot

Once power has been applied, U-Boot bootloader will be executed and the debug messages will be printed on the serial console. U-Boot automatically runs the autoboot macro, that loads the kernel/dtb and launches it with the options for mounting the root file system from the SD card.

At the end of the boot process, a demo application is launched and you can interact with the system using the touchscreen. The Linux shell is available on the serial console. Moreover, both telnet and ssh services are available to connect to the system through the network.

Serial console

A simple Windows serial and SSH/telnet client and terminal can be downloaded from here.

The following picture shows the serial setup for connecting to the EVK:

PuTTY connection using Serial Port

once selected the COM[x] serial port, click the Open button which starts the terminal. Once powered, the EVK shows the U-boot debug messages printed on the serial console.

Connecting through SSH

Once the ethernet port has been configured, the following picture shows the SSH connection to the EVK (in the following example, a 192.168.0.89. IP address is used):

PuTTY connection using SSH

once selected the IP address, click the Open button which starts the terminal. Once connected, the EVK shows the linux kernel prompt login for inserting the login:

PuTTY SSH login

Then use the root login username (there is no password):

PuTTY SSH connected

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Boot Configurations

AXEL Lite Evaluation Board is built upon i.MX6 family processor.

The following sections detail boot configuration options, which differ depending on the SoM.

For more information about AXEL Lite boot options, see the related page on AXEL Lite Hardware Manual.

Available options

Boot modes can be selected by J32 jumper switches which acts directly on J2.20 BOOT_MODE_SEL SOM pin.

Boot options order code	Jumper mounted	Jumper not mounted
Boot from NAND	SD	NAND
Boot from NOR	SD	NOR

Boot option

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Reset Button

AXEL Lite Evaluation Board has a pushbutton directly connected to the PMIC_PWRON signal which drives a SOM hardware reset.

S3 is the hardware reset button.

Reset button

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General Information

Product Highlights

The SBCX platform presented here provides a compact solution for any industry and can be easily interfaced with Plant Automation Control thanks to IEC-61131 SW language environment and/or other plug-ins like QT framework, Chromium web based GUI or multimedia GStreamer video applications.

The following table summarizes the main hardware and software features available with SBCX:

Hardware

Subsystem	Characteristics
CPU	NXP i.MX6 Solo/Dual/Quad core
USB	Host and device
Serial Ports	RS232/422/485 mutliprotocol LVTTL UART CAN interface
Ethernet	10/100/1000Mbps
Display	Dual LVDS interface WIDE TM interface with 24bit RGB
Video	HDMI and MIPI (optional) interfaces
Touchscreen	Resistive and capacitive
Audio	Stereo OUT and MIC in (on 2x2.54mm connector)
Connectivity	Bluetooth and Wi-Fi
PSU	12 to 24V DC
Mechanical Dimensions	85x156mm - Standard DIN (9modules)

Software

Subsystem	Options
Operating System	Linux, Android
Distribution	Yocto, Debian, Buildroot
Graphical Framework	Qt, Android, Chromium browser
Applications	SoftPLC, IoT runtime, nodeJS

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Block diagram

The following picture shows a simplified block diagram of the AXEL Lite SOM Evaluation kit.

Main functional subsystems and interfaces are depicted.

AXEL Lite Evaluation kit Block diagram

The heart of the Evaluation Kit is the AXEL Lite SOM module: please refer to the following Product Highlights page for the Evaluation Kit product highlights information.

Here below a summary for the main characteristics of the Kit.

Features Summary

Feature	Specifications
Supported SOM	NXP i.MX6 SOM
Serial Ports	1x UART RS232/RS422/RS485 1x LVTTL UART 1x UART RS232 on pin strip (debug port)
Connectivity	1x Fast Ethernet on RJ45 connector 1x CAN port with PHY DWM Wireless module (optional)
Display	2x LVDS HDMI WIDE™ display interface
Storage	1x microSD slot
USB	1x USB 2.0 Host port 1x USB OTG port
Audio	TLV320AIC310 codec
Miscellaneous	Resistive 4-wire touch controller GPIOs JTAG RTC battery

Electrical, Mechanical and Environmental Specifications

Electrical / Mechanicals	Specifications
Supply voltage	+ [12 - 24] V
Dimensions	156 mm x 84 mm
Weight	107,6 g
Operating Temperature	0..70 °C

(*) WIDE™ = Wise Interface Display Expander

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Interfaces and Connectors

Power Supply

Description

Power is provided through the J2 connector. Power voltage range is +[12-24 V].

J2 is a two pins MSTBA 2.5/2-G-5.08 Phoenix connector.

Power Supply connector

Signals

The following table describes the interface signals:

Pin#	Pin function	Pin Notes
1	DGND	Ground
2	VIN	+[12-24 V]

Power LED

DL1 is a green LED (placed near battery holder) shows the status of the power input. This LED is ON when a valid power supply is present.

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CPU connector

Description

J10 is the 204-pins SODIMM mating connector for the AXEL LITE SOM.

CPU connector

For a detailed description of the SOM pinout, please refer to the AXEL Lite SOM Hardware Manual.

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On board JTAG connector

JTAG signals are routed to a dedicated connector on the AXEL Lite PCB.

The connector is placed on the top side of the PCB, at the upper-right corner (please see the picture below).

J7 - SOM Connector's pinout

J7 footprint mates with Samtec FSI-110-03-G-S connector. The following table reports the connector's pinout:

JTAG connector

Pin#	Pin name	Function	ARM-20 JTAG	Notes
1	DGND	-	4,6,8,10,12,14,16,18,20	For example documented on Lauterbach specification
2	JTAG_TCK	-	9	-
3	JTAG_TMS	-	7	10K pull-up to 3V3 (BOARD_PGOOD driven signal)
4	JTAG_TDO	-	13	10K pull-up to 3V3 (BOARD_PGOOD driven signal)
5	JTAG_TDI	-	5	10K pull-up to 3V3 (BOARD_PGOOD driven signal)
6	JTAG_nTRST	-	3 (*)	10K pull-up to 3V3 (BOARD_PGOOD driven signal)
7	CPU_PORn	-	15 (*)	-
8	N.C.	-		-
9	N.C.	-		-
10	JTAG_VREF	-	1	3V3 (BOARD_PGOOD driven signal)

(*) keep the possibility to be unconnected

JD1 - EVB Connector's pinout

JD1 is a 10x1x2.54mm pinhole header. The following table reports the connector's pinout:

EVB JTAG connector

Pin#	Pin name	Function	Notes
1	DGND	-
2	JTAG_TCK	-	-
3	JTAG_TMS	-	10K pull-up to 3V3 (BOARD_PGOOD driven signal)
4	JTAG_TDO	-	10K pull-up to 3V3 (BOARD_PGOOD driven signal)
5	JTAG_TDI	-	10K pull-up to 3V3 (BOARD_PGOOD driven signal)
6	JTAG_nTRST	-	10K pull-up to 3V3 (BOARD_PGOOD driven signal)
7	JTAG_nRST	-	-
8	N.C.	-	-
9	N.C.	-	-
10	JTAG_VREF	-

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Ethernet

Description

J16 is a standard RJ45 connectors connected to the SOM integrated ethernet controller and PHY.

Ethernet connector

Signals

The following table describes the interface signals:

Pin#	SOM Pin#	Pin name	Pin function	Pin Notes
11	J10.19	ETH0_TXRX0_P	Transmit and receive pair 0 data +
10	J10.21	ETH0_TXRX0_M	Transmit and receive pair 0 data -
4	J10.23	ETH0_TXRX1_P	Transmit and receive pair 1 data +
3	J10.27	ETH0_TXRX2_P	Transmit and receive pair 2 data +
2	J10.29	ETH0_TXRX2_M	Transmit and receive pair 2 data -
5	J10.25	ETH0_TXRX1_M	Transmit and receive pair 1 data -
8	J10.31	ETH0_TXRX3_P	Transmit and receive pair 3 data +
9	J10.33	ETH0_TXRX3_M	Transmit and receive pair 3 data -
17	J10.15	3V3_ETH1_LED2	Eth link led
20	J10.13	3V3_ETH1_LED1	Eth activity led

Device mapping

The network interface mapped at eth0 device in Linux.

Device usage

The peripheral is used the standard kernel interface and network protocol stack.

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Console interface

Description

The Console interface available on the Evaluation Kit at the connector J22.

J22 is a 10 pin (5x2x2.54mm) header connector for the RS232 two-wires UART3 port, used for debug purposes (bootloader and operating system serial console).

Console connector

Signals

The following table describes the interface signals:

Pin#	SOM Pin#	Pin name	Pin function	Pin Notes
1,2,4,6,,7,8,10	-	N.A.	N.C.	Not connected
3	J10.189	RS232_RX	Receive line
3	J10.187	RS232_TX	Transmit line
9	-	DGND	Ground

Device mapping

UART3 is mapped to /dev/ttymxc2 device in Linux. The peripheral is used as the default serial console, both for the bootloader and the kernel.

Device usage

To connect to the debug serial port:

1. connect the DB9 adapter bracket to the J22 connector on the SBCX board
2. connect a serial cable between DB9 connector and PC COM port through a NULL-modem cable (not provided)
3. start your favorite terminal emulator software on PC (eg: PuTTY); communication parameters are: 115200,N,8,1

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UARTs interface

Description

The UARTs interface available on the Evaluation Kit are mapped to the following connectors:

• J25 is a 6x1x2.54mm horizontal socket header for the UART4 port. This is a Digilent Pmod™ Compatible connector for the UART Pmod™ Compatiblemodule (6-Pin Pmod™ Compatible Connector Digilent Pmod™ Interface Specification Type 4 UART)

PMOD configuration

• J21 is a standard DB9 male connector for the configurable UART5 port. The board provides some configuration options for the selection of the UART mode (RS232/RS422/RS485 with auto-direction)

DB9 configuration

Signals

The following tables describes the interface signals

UART4

Pin#	SOM Pin#	Pin name	Pin function	Pin Notes
1	J10.50	PMOD_A0	Clear to send
2	J10.89	PMOD_A1	Transmit data
3	J10.91	PMOD_A2	Receive data
4	J10.40	PMOD_A3	Request to send
5	-	DGND	Ground
6	-	3V3	+3.3 V

UART5

Pin#	SOM Pin#	Pin name	RS-232	RS-422	RS-485
1	-	Not connected	Not connected	Not connected	Not connected
2	J10.95	UART5_A	UART5 receive line	UART5_A	UART5_A
3	J10.93	UART5_Y	UART5 transmit line	UART5_Y	UART5_A
4	-	Not connected	Not connected	Not connected	Not connected
5	-	DGND	Ground	Ground	Ground
6	-	Not connected	Not connected	Not connected	Not connected
7	J10.105	UART5_Z	UART5 Request To Send	UART5_Z	UART5_B
8	J10.107	UART5_B	UART5 Clear To Send	UART5_B	UART5_B
9	-	Not connected	Not connected	Not connected	Not connected

The J19 and J20 jumpers are used to configure the UART mode, as reported below:

Jumper	RS232 mode	RS422 mode	RS485 mode
1-3	open	open	closed
5-7	open	closed	open
9-11	open	closed	open
2-4	open	open	closed
6-8	open	closed	closed
10-12	open	closed	closed
13-15	open	open	closed
14-16	open	open	closed

J19 and J20 connectors

UART5 jumper configuration

Device mapping

• UART4 is mapped to /dev/ttymxc3 device in Linux
• UART5 is mapped to /dev/ttymxc4 device in Linux

Device usage

• UART4 can be used with a PMOD adapter or with a TTL peripheral
• UART5 is a MultiProtocol that support (after harware Jumper configuration) the RS232, RS4222 or RS485 protocols. The related device tree file has to be properly configured too for enabling the GPIO transceiver configuration, see Configuring the RS232/RS485 mode

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micro SD interface

Description

The micro SD interface available on the Evaluation Kit at the connector J26.

J26 is a Micro-SD card header. This interface is connected to the USDHC1 controller of the i.MX6 CPU.

microSD connector

Signals

The following table describes the interface signals:

Pin#	SOM Pin#	Pin name	Pin function	Pin Notes
1	J10.79	SD_DAT2	Data 2
2	J10.81	SD_DAT3	Data 3
3	J10.83	SD_CMD	CMD
4	-	3V3	+3.3 V
5	J10.85	SD_CLK	Clock
6, 12	-	DGND	Ground
7	J10.75	SD_DAT0	Data 0
8	J10.77	SD_DAT1	Data 1
9, 10, 11	-	SD_SHIELD	Shield
13	J10.177	EIM_D19	Card detect

Device mapping

The microSD card is mapped to /dev/mmcblk0. The available partitions are shown as /dev/mmcblk0p1, /dev/mmcblk0p2, etc.

Device usage

The device can be mounted/accessed as a standard block device in Linux.

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USB ports

Description

SBCX provides two USB ports, one Host and one device:

• J17 is a standard USB Host 2.0 Type A connector

USB Host connector

• J18 is a micro-AB type receptacle for a USB device connection: this interface can operate in Device (peripheral) mode and - optionally - in Host mode

USB device connector

Signals

The following table describes the interface signals

USB Host

Pin#	SOM Pin#	Pin name	Pin function	Pin Notes
1	J10.188	USB_HOST_VBUS	VBUS
2	J10.202	USB_HOST_DN	USB Host Data -
3	J10.200	USB_HOST_DP	USB Host Data +
4	-	DGND	Ground

USB Device

Pin#	SOM Pin#	Pin name	Pin function	Pin Notes
6, 7, 8, 9	-	USB_OTG_SH Shield
1	J10.186	USB_OTG_VBUS	VBUS	This pin can be powered (for Host mode) (*)
2	J10.196	USB_OTG_DN	USB OTG Data -
3	J10.198	USB_OTG_DP	USB OTG Data +
4	J10.192	ENET_RX_ER	USB OTG ID
5	-	GND	Ground

Device usage

The USB Host port can be used under Linux for connecting USB peripheral devices: the related peripheral driver has to be integrated into the Linux kernel.

The USB Device feature can be easily tested using the Mass Storage Gadget driver. (*) This port can operate in Host mode using a proper BOM mount option. See the EVK schematics for more info

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LVDS

Description

SBCX provides two LVDS interfaces, LVDS0 and LVDS1.

• J8 is a Hirose (cod. DF13A-20DP-1.25V) double row 1.25mm pitch miniature crimping connector
• J9 is a Hirose (cod. DF13A-20DP-1.25V) double row 1.25mm pitch miniature crimping connector

LVDS connectors

Signals

The following tables describes the interface signals

LVDS0

Pin#	SOM Pin#	Pin name	Pin function	Pin Notes
1, 2	-	3.3V_LCD0	3.3 V
3, 4, 7, 10, 13, 16, 19	-	DGND	Ground
5	J10.137	LVDS0_TX0_N	LVDS Data 0 -
6	J10.139	LVDS0_TX0_P	LVDS Data 0 +
8	J10.141	LVDS0_TX1_N	LVDS Data 1 -
9	J10.143	LVDS0_TX1_P	LVDS Data 1 +
11	J10.145	LVDS0_TX2_N	LVDS Data 2 -
12	J10.147	LVDS0_TX2_P	LVDS Data 2 +
14	J10.133	LVDS0_CLK_N	LVDS Clock -
15	J10.135	LVDS0_CLK_P	LVDS Clock +
17	J10.149	LVDS0_P17	Mount options	LVDS0_TX3_N option
18	J10.151	LVDS0_P18	Mount options	LVDS0_TX3_P option
20	J10.46	LVDS0_P20	Mount options	GND or PWM (J10.46) option

LVDS1

Pin#	SOM Pin#	Pin name	Pin function	Pin Notes
1, 2	-	3.3V_LCD0	3.3 V
3, 4, 7, 10, 13, 16, 19	-	DGND	Ground
5	J10.159	LVDS1_TX0_N	LVDS Data 0 -
6	J10.161	LVDS1_TX0_P	LVDS Data 0 +
8	J10.163	LVDS1_TX1_N	LVDS Data 1 -
9	J10.165	LVDS1_TX1_P	LVDS Data 1 +
11	J10.167	LVDS1_TX2_N	LVDS Data 2 -
12	J10.169	LVDS1_TX2_P	LVDS Data 2 +
14	J10.155	LVDS1_CLK_N	LVDS Clock -
15	J10.157	LVDS1_CLK_P	LVDS Clock +
17	J10.171	LVDS1_P17	Mount options	LVDS1_TX3_N option
18	J10.173	LVDS1_P18	Mount options	LVDS1_TX3_P option
20	J10.46	LVDS1_P20	Mount options	GND or PWM (J10.46) option

Device mapping

• LVDS0 is mapped to /dev/fb0 device in Linux
• LVDS1 is mapped to the corresponding device driver in Linux, depending on the ldb peripheral configuration in the device tree. The default value is disabled but can be mapped to /dev/fb2 (second and independent LCD panel) or can be the second LVDs channel for a dual-channel LCD panel configuration (like a 1920x1080 DUAL LVDS channel LCD panel)

Power sequence

Most of the LCD panels have many supplies and need a specific timing to power the rails and start the signals.

The Evaluation Kit provides GPIO controlled power rails that can be leveraged both at bootloader and kernel level to meet any specifications.

The following sections describe the available rails:

3V3_LCD

The most common voltage to supply the LCD panel internal logic:

• rail 3V3_LCD0 is enabled by GPIO1_IO00
• rail 3V3_LCD1 is enabled by GPIO1_IO02

5V_LCD

The most common voltage to supply the LCD panel backlight:

• rail 5V_LCD0 is enabled by SD3_DATA1
• rail 5V_LCD1 is enabled by SD3_DATA0

Device usage

The associated framebuffer device is accessed in Linux through the standard graphic access.

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Touchscreen

Description

The 4-wire resistive touch controller signals are routed to J50, which is a 4 pin (1mm pitch vertical) ZIF connector for the 4-wires resistive controller.

The touch controller is a TI TSC2003 device, connected to the I²C2 bus (address 0x1001000b).

Touchscreen connector

Signals

The following table describes the interface signals:

Pin#	SOM Pin#	Pin name	Pin function	Pin Notes
1	-	TSC_YP	Touch controller Y+
2	-	TSC_XP	Touch controller X+
3	-	TSC_YM	Touch controller Y-
4	-	TSC_XM	Touch controller X-

Device mapping

The device is typically mapped to /dev/touchscreen0 device in Linux.

The touch controller is attached to the generic Linux input event interface (evdev).

Device usage

The simplest tools for touch screen management are the tslib library and ts_tools utilities. To calibrate the touch screen, the ts_calibrate command line tool is available. After calibration, the touch screen can be tested using the graphical ts_test utility or the ts_print command line tool.

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HDMI

Description

SBCX provides an HDMI 1.4a compatible interface, including the HDMI controller and PHY, routed to a standard HDMI Type A receptacle.

HDMI connectors

Signals

The following table describes the interface signals:

Pin#	SOM Pin#	Pin name	Pin function	Pin Notes
1	J10.125	HDMI_D2P	TX pair 2 data +
3	J10.123	HDMI_D2N	TX pair 2 data -
4	J10.121	HDMI_D1P	TX pair 1 data +
6	J10.119	HDMI_D1N	TX pair 1 data -
7	J10.117	HDMI_D0P	TX pair 0 data +
9	J10.115	HDMI_D0N	TX pair 0 data -
10	J10.113	HDMI_CLKP	Tx pair clock +
12	J10.111	HDMI_CLKN	Tx pair clock -
13	J10.127	CE_REMOTE_OUT	Consumer Electric Control
15	J10.101	DDC_CLK_OUT	I2C clock
16	J10.103	DDC_DAT_OUT	I2C data
18	-	5V	+5V output	Internally limited to 135mA
19	J10.129	HDMI_HP_OUT	Hotplug detection
2, 5, 8, 11, 17	-	DGND	Ground
14	-	NC	Not connected
20, 21, 22, 23	-	SH_HDMI	Shield

Device mapping

HDMI video is mapped to the corresponding device driver in Linux, depending on the device tree configuration. If this is the only video output, then the default value is mapped to /dev/fb0.

Device usage

The associated framebuffer device is accessed in Linux through the standard graphic access.

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MIPI

Description

J34 is a 20x2x1.00 mm One Piece Interface dedicated to the MIPI camera input and the PCI Express expansion bus interface.

This connector can be used as a Camera Interfacefor connecting a MIPI CSI-2 camera device.

Signals

The following table describes the interface signals:

Pin#	SOM Pin#	Pin name	Pin function	Pin Notes
1	-	5V_IN
3	J10.97	AUX_PWR_EN		connected to GPIO4_IO10 (KEY_COL2)
13	-	AUX_USB_DN
15	-	AUX_USB_DP
19	J10.53	CAM_PWD
20	-	3V3
21	J10.51	CAM_RSTn
22	J10.60	CAM_CLK
25	J10.102	CSI_CLK0M_1
26	J10.48	CSI_SDA
27	J10.104	CSI_CLK0P_1
28	J10.38	CSI_SCL
31	J10.110	CSI_D1M_1
32	J10.106	CSI_D0M_1
33	J10.112	CSI_D1P_1
34	J10.108	CSI_D0P_1
37	J10.118	CSI_D3M_1
38	J10.114	CSI_D2M_1
39	J10.120	CSI_D3P_1
40	J10.116	CSI_D2P_1
5, 8, 11, 14, 17, 23, 24, 29, 30, 35, 36	-	DGND	Ground

Device mapping

The MIPI CSI peripheral is mapped to the corresponding /dev/video<X> device in Linux. The device mapping depends on the device tree configuration.

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PCIe

Description

J34 is a 20x2x1.00 mm One Piece Interface dedicated to the MIPI camera input and the PCI Express expansion bus interface.

Signals

The following table describes the interface signals:

Pin#	SOM Pin#	Pin name	Pin function	Pin Notes
1	-	5V_IN
2	J10.64	PCIE_WAKE_B
3	J10.97	AUX_PWR_EN		connected to GPIO4_IO10 (KEY_COL2)
4	J10.76	PCIE_RST_B
6	J10.74	PCIE_DIS_B
7	J10.84	PCIE_CLKN
9	J10.86	PCIE_CLKP
10	J10.92	PCIE_RXN_R
12	J10.94	PCIE_RXP_R
16	J10.96	PCIE_TXN_C
18	J10.98	PCIE_TXP_C
20	-	3V3
25	J10.102	CSI_CLK0M_1
26	J10.48	CSI_SDA
28	J10.38	CSI_SCL
5, 8, 11, 14, 17, 23, 24, 29, 30, 35, 36	-	DGND	Ground

Device mapping

The PCI express peripheral is mapped to the corresponding device in Linux depending on the associated kernel device driver and on the device tree configuration.

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CAN

Description

The CAN interface available on the Evaluation Kit at the connector J23.

J23 is a 3x2x2.54mm header that provides the CAN bus port compatible with the CAN 2.0B protocol. The CAN transceiver is implemented on the AXEL LITE SOM.

CAN connector

Signals

The following table describes the interface signals:

Pin#	SOM Pin#	Pin name	Pin function	Pin Notes
1,2	-	N.A.	N.C.	Bus termination
3	J10.44	CAN_M	Low bus line
4	J10.42	CAN_P	High bus line
5	-	CAN_SHIELD	Shield
6	-	DGND	Ground

Device mapping

CAN device is mapped to can0 device in Linux. The peripheral can be configured using ifconfig and ip link utilities.

Device usage

Inserting a jumper on pins 1 and 2 enables 120Ω bus termination.

CAN electrical connections

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Audio

Description

The Audio interface available on the Evaluation Kit at the connector J27.

J27 is a 7x2x2.54mm header. The audio codec is a TLV320AIC3100 device connected to the I²S interface.

Audio connector

Signals

The following table describes the interface signals:

Pin#	Pin name	Pin function	Pin Notes
4, 5, 8, 9	AGNDM Analog	Ground
1	AUX_RES	Analog ground
2	AUXR	Microphone in right
3	AUXL	Microphone in left
6	SPKM	Speaker out (negative)
7	SPKP	Speaker out (positive)
10	HSOR	Audio Headset right
11	HSOL	Audio Headset left
12	MIC_BIAS	Microphone bias
13	AUD_HP_VGND	Analog ground

Device mapping

The Audio interface is mapped to card0 ALSA device in Linux. The ALSA peripheral #0: sbcx-audio-tlv320aic3100 can be accessed via alsa-utils with hardware address 0.

Device usage

For example, it is possible to play a file using aplay -D hw:0,0 device access.

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RTC

Description

SBCX uses the RTC device provided by AXEL Lite PMIC

An external lithium battery (like Panasonic ML-2020/G1AN rechargeable battery) can be optionally mounted on SBCX.

Lithium battery

Signals

The following table describes the interface signals:

Pin#	SOM Pin#	Pin name	Pin function	Pin Notes
-	J10.14	PMIC_LICELL		coin cell battery network has to be properly configured for lithium battery recharge current

Device mapping

RTC is mapped to /dev/rtc0 device in Linux.

Device usage

The peripheral can be accessed through the date and hwclock linux commands.

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DWM

Description

J24 is a 30-pins 0.50mm Pitch SlimStack™ Receptacle. This connector is dedicated to the DWM optional add-on module.

The module is built around an LS Research TiWi-BLE Integrated Transceiver Modules for WLAN 802.11 b/g/n and Bluetooth. The module implements the necessary PHY/MAC layers to support WLAN applications in conjunction with a host processor over a SDIO interface. The module also provides a Bluetooth platform through the HCI transport layer. Both WLAN and Bluetooth share the same antenna port.

DWM connector

Signals

The following table describes the interface signals:

Pin#	SOM Pin#	Pin name	Pin function	Pin Notes
1, 2	-	5V
3, 4	-	3.3V
5, 6, 9, 10, 19	-	DGND	Ground
7	J10.69	TIWI_MMC2_CMD
8	J10.71	TIWI_MMC2_CLK
11	J10.61	TIWI_MMC2_DAT0
13	J10.63	TIWI_MMC2_DAT1
15	J10.65	TIWI_MMC2_DAT2
17	J10.67	TIWI_MMC2_DAT3
21	J10.47	UART2_RX		Used only for BT peripheral
23	J10.55	UART2_CTS		Used only for BT peripheral
24	J10.39	TIWI_BT_F5
25	J10.49	UART2_TX		Used only for BT peripheral
26	J10.41	TIWI_BT_F2
27	J10.59	UART2_RTS		Used only for BT peripheral
28	J10.43	TIWI_IRQ
29	J10.99	TIWI_BT_EN
30	J10.45	TIWI_EN
12, 14, 16, 18, 20, 22	-	N.C.	Not connected

Device mapping

The WiFi peripheral is mapped to the corresponding wlan<X> device in Linux. The network peripheral is visible under the ifconfig network configuration utility.

Device usage

The peripheral is used the standard kernel interface and network protocol stack.

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GPIOs

Description

i.MX6 can handle external pins in many different ways and most of them can be configured as GPIOs. When a pin is set as a GPIO, it is possible to read its value, change its direction or change output value directly from the shell.

Signals

The following table describes some GPIOs signals available on J33 WIDE™ connector:

Pin#	SOM Pin#	Pin name	Pin function	Pin Notes
28	J10.191	EIM_D26		GPIO3_IO26
30	J10.193	EIM_D27		GPIO3_IO27
32	J10.50	GPIO_17		GPIO7_IO12
34	J10.40	GPIO_6/I2C3_SDA		GPIO1_IO06

Device mapping

GPIOs can be used directly on Linux kernel device driver or can be configured on the device tree.

Device usage

See the GPIOs page on the DESK-MX6-L Software Manual.

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Electrical and Mechanical Documents

Please find here below the links for the AXEL Lite Evaluation Kit schematics and the related documents (BOM and layout):

Schematics

• AXEL Lite EVK ORCAD DSN schematics
• AXEL Lite EVK PDF schematics

BOM

• AXEL Lite EVK BOM

Layout

• AXEL Lite EVK Assembly view

Mechanical specifications

This page describes the mechanical characteristics of the SBCX board.

Board layout

Assembly view: top

Assembly view: bottom

Dimensions

CAD drawings

• STEP (3D): SBC AXEL.step

Mechanical data

Dimension	Value
Width	156 mm
Depth	84 mm
Max component's height (top)	13.87 mm
Max component's height (bottom)
PCB height	1.69 mm