What is FET6254-C System on Module(SoM)?

FET6254-C SoM of Forlinx Embedded is designed and developed based on TI Sitara™ AM62x series industrial-grade processors, ARM [email protected] with rich interface resources. It can be widely used in industrial such as human machine interface (HMI), edge computing, vending machine, EV charging control unit (TCU) and medical equipment.

Following are AM62x performance tests

1. AM335x VS AM62x

Compared with AM335x, AM62x has richer functions and more powerful performance.

	AM335x	AM62x
CPU	Single-Core Cortex-A8, 1Ghz	Quad-Core Cortex-A53, 1.4Ghz Cortex-M4F
GPU	1.6G FLOPS, OpenGL ES 2.0	8G FLOPS, OpenGL ES 3.1
Interface	UART*6, CAN*2, I2C*3, SPI*2, GPMC-100MHz	UART*9, CAN-FD*3, I2C*6, SPI*4, GPMC-133MHz, OSPI/QSPI*1, MIPI CSI*1
Display	Single channel RGB888, up to 1080P30	Dual-channel DPI+LVDS, support three-screen display, up to 2K
Network	ETH*2	ETH*2, support IEEE1588

We tested AM335x and AM62x respectively by Nbench. The running scores are as follows:

AM335x benchmark result

AM62x benchmark result

Compared with AM335x, AM62x has 2.6 times higher integer processing and 3.6 times higher floating point processing. AM62x’s performance is much more powerful.

2. AM62x function test

2.1. IEEE 1588 Precision Time Test (PTP)

Precision Time Synchronization Protocol plays an important role in control system. With the continuous application growth of embedded control system, the clock synchronization of each distributed node in the synchronization system becomes more and more important. Some highly time-sensitive industrial clusters require high-precision time synchronization to ensure the normal operation of cluster.

The general Network Time Synchronization Protocol (NTP) can only keep time difference within milliseconds, which cannot meet the requirements of time accuracy. AM62x supports IEEE1588 precise time synchronization protocol, which can reduce time difference among devices to within nanoseconds (ns).

Next, let’s have a test. Here we have two development boards, one as master and the other as slave (testing machine).

Master(Left) and testing machine(Right)

root@ok6254:~# ethtool -T eth1  #Check whether network card supports PTP
root@ok6254:~# ptp4l -E -2 -H -i eth1 -m # host is set as master clock
root@ok6254:~# ptp4l -E -2 -H -i eth1 -m -s #slave is set to slave clock

Master offset in the figure is master-slave time difference defined in PTP protocol, unit is ns. It can be seen when timing is stable, time difference between two development boards is within a few tens of nanoseconds. The time difference is very small.

2.2 M core independent running test

AM6254 is a heterogeneous multi-core processor, Cortex-A53 processing core and Cortex-M4F control core. Functional safety features are realized by M4F and its dedicated peripherals. And the startup and operation of M4F no longer depend on A53, making it more stable and flexible.

In practical applications, the program of M core runs on bare machine or simple operating system. So M core has fast running speed and high stability. It is generally used for simple but important control, such as fault handling, switch control.

Linux is running in A core. The relatively complex system means the risk of crash and restart is relatively higher. Its stability and speed are not as good as M core, but A core has rich and powerful functions and can achieve many functions which M core cannot, such as data collection, data processing.

M core depends on operation of A core for many current dual-architecture embedded processors. When Linux in A core crashes, M core cannot work normally, and the important work M core is responsible for cannot be maintained. M-core and A-core of AM62x are independent of each other. The operation of A core has no influence on M-core. Its stability is greatly improved.

Turn on Flow LED of M core:

root@ok6254:~#cd/sys/class/remoteproc/remoteproc0
root@ok6254:/sys/class/remoteproc/remoteproc0#
echom4fss_firmware/forlinx_gpio.release.out > firmware
root@ok6254:/sys/class/remoteproc/remoteproc0#echostart > state

M core and A core run together (green LED and blue LED)

Restart A core

root@ok6254:~#fltest_reset_a53.sh

M core runs independently. When A core restarts, green LED is on, blue LED is off

2.3 GPMC NOR Flash read and write test

Format GPMC NOR Flash

root@ok6254:/#cat/proc/mtd
root@ok6254:/#flash_erase-j /dev/mtd0 0 0

Mount NOR Flash to file system

root@ok6254:/#mount-t jffs2 /dev/mtdblock0 /mnt/

NOR Flash read and write test

root@ok6254:/#dd if=/dev/zero of=/dev/mtdblock0 bs=1M count=16 conv=fsync

Write:

Read:

From the test results, write and read speeds of AM62x are "257KB/s" and "10.8MB/s" respectively.

3. Conclusion

From above comparison and tests, FET6254-C SoM with TI Sitara™ AM62x has a huge improvement of performance and function, compared to FET335xD, and is also Pin2Pin with FET335xD-C.
AM62x provides a life cycle of 10+ years. Long-life cycle support for medical, industrial.
It is a very good choice to replace AM335x which has been on sale for ten years with AM62x.