ADI Trinamic modules use the standard 8N1 bit format with a default telegram pause time of zero. For communication, a so-called Master-Slave pattern is being used. So a PC or MCU (Master) sends a request command of 9 Byte, and the module (Slave) answers with a reply command of 9 Byte. After this reply command, the Master can send the next command.
Most Significant Bit (MSB) or Least Significant Bit (LSB)?
For a first try, please use the TMCL-IDE. This free and easy to use GUI allows you to try all available commands in the "Direct Mode" when you connect the module using a USB-to-RS485 adapter. The TMCL-IDE has a command history mode, allowing you to see which commands are sent.