Starting MexBIOS on debugging kit TE-TMS320F28335 manufactured by Terraelectronica

Starting MexBIOS on add-in module developed and manufactured by Terraelectronica on basis of new 32-bit signal microcontroller TMS320F28335 Delfino manufactured by Texas Instruments is described.

Following directions from documentation file TMS320F2833x_Startup_help.pdf (the file is supplemented to the block library for processors TMS320F2833x) the following changes of the start project should be done:
  1. Change the clock frequency to 20 MHz, the system frequency of the processor computations will be changed respectively;
  2. Change discrete pins that are used for connection via USB;
  3. Change the data communication rate if needed;
Fig. 1. Connection circuit of the board TE-TMS320F28335 to a computer
  • To change the crystal frequency you need in file config.h to modify the following lines:
  • Lock the line with DSP28_DIVSEL 2 and unlock the line with DSP28_DIVSEL 3 In file DSP2833x_Init.c:
  • Function of pins is defined in file DSP2833x_Init.c. You need to modify the following:
  • Thereafter you should compile the project (in CCS go to Project->Build). 
  • Change settings of On-Chip Flash Programmer for the crystal frequency of 20 MHz:
Fig. 2. Settings of On-Chip Flash Programmer
Next you need to follow the procedure, as shown in instructions for loading the start project and the block library into Flash memory of the microcontroller. (Loading the start project of MexBIOS into TMS320F28335 Delfino)
  • In case of unstable communication of the MexBIOS kernel (the connection is broken during the process of loading the configuration file into memory of the microcontroller) and the computer you need to try:
  • Make sure that there is no source of electromagnetic interference nearby.
  • Disconnect JTAG from the board.
  • Use shielded USB cable.
  • Use RS-485 interface.
  • If none of the above mentioned helps (including use of RS-485), you may try to decrease the data communication rate. For example, change the rate to 19200.
  • To change the data communication rate you need to set the following lines in file main.c:
After each modification of the start project you need to compile and load the start project into the intended sectors of FLASH-memory of microcontroller.
  • After the start project and block library are loaded, in Connection settings  change the Baud rate to 19200:
Fig. 3. Connection settings in MexBIOS Development Studio