Function Test
ARM CPU Board for printing applications
Fct-test
The device under test
Interfaces to proof:
- RS232
- 2xUART
- 3xUSB-A 1xUSB-B
- SD-Card Slot
- 100MBit Ethernet
- 2xCAN Interface
- 10x Custom Sensor Interface
- GPIOs
- Over Current Protections
- 5V internally generated
- 3V3 internally generated
- 1V8 internally generated
- Acts like a gateway between host computer and device under test
- Power switches for power supply
- Analog switches for signal lanes
- I2C interface
- GPIO port expanders to control switches
- Analog digital converter to monitor voltages
- Polyfuses in case of fault
The device under test
In fact that this CPU board has standard interfaces like ethernet and RS232, we connected the device under test (DUT) directly to a normal computer.
The host computer writes the initial U-Boot into the RAM of the DUT and it becomes alive. After that the DUT boots from a USB stick ware a customized yocto OS including all test software is stored on.
The test itself is running on the device under test. The host and the DUT are communicating via TCP/IP and serial interfaces. The host monitors every single test and logs the whole console output from the DUT. All test results and the console output will be stored in a PDF file generated with python.
The host is running a ubuntu operating system so we were able to rapid prototype a simple test application, which is written in python. This includes a crude grafical user interface and automatic test reports in PDF, JSON and other file formats.
Some Pictures of the assembled FCT
