TileMCU FirmWare

The TileMCU Coldfire version completed its first set of tests, completing the integration of the USB stack from Freescale/NXP to the RTOS.

Using POSIX-style drivers (or any standard way of interfacing) we were able to replace the Serial input of the Command Line Interpreter (CLI) with the USB one.

The code change was a very simple one, replacing just the name of the driver.

Code Excerpt of Selectable Driver

So essentially we define a preprocessor macro with the name of the required driver. As both the USB-CDC and the Serial driver have the same API, they can be interchanged at will.

Here we do this on compile time. Another option would be to mirror both interfaces and have at the same time either USB or Serial I/O. For now, we decided to keep it simple as we have to test the rest of the boards to complete our hydrophone system.

USB Enumeration

At first, the USB enumeration was checked to see if the basics worked. Then we opened with our terminal the respective virtual serial port and start testing the CLI.

CLI Test Example

The CLI was tested to ensure that there were no problems using it and testing some other functions like the SD Card mounting and FAT access.

As we have completed the first phase of testing we can move on to the next boards for testing. We will return back to this board to test the Mini-FlexBus interface with the FPGA.

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