Trip Zone Force Register

Hello,

I am using the High Voltage Motor Control and PFC kit with a Piccolo (http://www.ti.com/tool/tmdshvmtrpfckit).  I need to set up a trips function to shut down power to the motor in certain circumstances.

Using the One Shot Trip function seems like a great way to go, and it can (supposedly) be set in software like this:

EPwm1Regs.TZFRC.OST = 1;

However, when I compile, I get an error: union "TZFRC_REG" has no field "OST"

However, there clearly is:

//----------------------------------------------------
// Trip zone flag force register bit definitions */
struct TZFRC_BITS {         // bits   description
   Uint16  rsvd1:1;         // 0      reserved
   Uint16  CBC:1;           // 1      Trip Zones Cycle By Cycle Int
   Uint16  OST:1;           // 2      Trip Zones One Shot Int
   Uint16  DCAEVT1:1;       // 3      Force DCAEVT1 event
   Uint16  DCAEVT2:1;       // 4      Force DCAEVT2 event
   Uint16  DCBEVT1:1;       // 5      Force DCBEVT1 event
   Uint16  DCBEVT2:1;       // 6      Force DCBEVT2 event
   Uint16  rsvd2:9;        // 15:7   reserved
};

(That is out of DSP2803x_EPWM.h which is included in PeripheralHeaderIncludes.h which is included in the main C file, all stock TI code).

Anyone know why I am getting this error?

Jim