LAUNCHXL2-RM57L: SPI transmitting and receiving data rate setting.

Richard Dualmann14

Part Number: LAUNCHXL2-RM57L
Other Parts Discussed in Thread: HALCOGEN, C2000WARE

I am using the LAUNCHXL2-RM57L connects to F28377D via SPI and each MCU has to be Slave or Master bi-directional setting.

Given the F28377D clock rate of SPI is 50MHz in High-speed mode and the SPI clock rate is set under 1/4th of its maximum rate (i.e. 82.5MHz) in general,

That is, for compromising reasons, the SPI clock rate has to be under 50MHz is right?

If right, how can I use the GUI tool "HalCoGen" for doing this setting?

Thanks.

over 7 years ago

0 QJ Wang over 7 years ago

TI__Guru**** 196306 points

Hello Richard,

The maximum SPI clock that RM57 supports is 25MHz.

If you want to configure the MCU as slave, please uncheck teh "master" in HALCoGen GUI:

0 Richard Dualmann14 over 7 years ago in reply to QJ Wang

Intellectual 370 points

Thanks for your response quickly.
The further question is can I get two SPI channels connected to the same SPI bus provided by F28377D, for example, SPIa physically?
If yes, I set the SPI1 to be a master and SPI2 in slave mode respectively.

0 QJ Wang over 7 years ago in reply to Richard Dualmann14

TI__Guru**** 196306 points

Hello Richard,

Sure, but there is big risk of fails, you need special code in each master (SPI1) and F28x SPI to manage the bus arbitration, to avoid "mast to master" situation.

Use one GIO pin of F28 device to allow the SPI1 (Master) to drive the clock pulse. When F28 is master, pull the GIO high to tell the SPI1 (master) to hold the clock signal.

Use different CS for SPI1 and SPI2.

0 QJ Wang over 7 years ago in reply to QJ Wang

TI__Guru**** 196306 points

Connect one F28x GIO pi to SPI1 (Hercules) nSPIENA pin.

0 Richard Dualmann14 over 7 years ago in reply to QJ Wang

Intellectual 370 points

Thank you so much.
After this week,
I get the launchpad and try it.
For F28x, the SPI setting have some bugs in control suite but in C2000ware 1.0.2, there are two SPI examples with external connection work fine.

Arm-based microcontrollers

Arm-based microcontrollers forum

LAUNCHXL2-RM57L: SPI transmitting and receiving data rate setting.