Hercules MibSPI C2TDELAY

Jason Pitteman

Other Parts Discussed in Thread: HALCOGEN

Hello,

I'm using the XRM57 microcontroller. I have to communicate with a gyroscope which needs a specific time of minimum 25 microseconds between the chip select going low and the start of the clock signal.

In HALCoGen it is only possible to set the value of C2TDELAY between 0 and 255, which means that the maximum delay is 3426.667 nano seconds. How can I have a longer delay?

I also need a longer delay for T2CDELAY. This delay must be minimum 5 microseonds and in HALCoGen I can only reach 3413.333 nano seconds.

How can I have a longer delay for both parameters?

Thanks in advance,

Jason

over 9 years ago

0 Bob Crosby over 9 years ago

TI__Guru 72500 points

With such long delays required I think you will need to configure the chip select as a digital I/O, drive it low, then set a timer (RTI) for 25uS delay, then do the SPI transfer, set the timer for 5uS delay, then set the CS high.

0 Anthony F. Seely over 9 years ago

TI__Guru 68920 points

Jason,

What clock frequency (SPICLK) does the Gyro require.
We've got an expectation that the clock frequency and the delays are in the same 'ballpark'. So slowing down the SPICLK for the Gyro would be what I would expect as a solution.

-Anthony