Question about OMAPL138 SPI

____-__-__

Dear E2E:

I found that both the SPI_DAT0[15:0] and SPI_DAT1[15:0] are defined as the transmision buffer. I wonder is there any differrences between them, and which one should i use in normal operation?

Thanks,

Huang.

over 13 years ago

0 Rahul Prabhu over 13 years ago

TI__Guru** 116170 points

Huang,

The last 16 bits of both the registers are linked and will reflect the same value when you write to TXDATA in them but SPI_DAT1 provides additional formatting options so for convenience of programming only one register, I would recommend using SPIDAT1 as suggested by most of the documentation as well as driver code in Starterware and BIOS PSP.

Regards,

Rahul

0 ____-__-__ over 13 years ago in reply to Rahul Prabhu

Intellectual 780 points

Dear Rahul Prabhu:

Thanks a lot for your reply. I have another question about the CSHOLD bit of SPIDAT1. This bit is described that "The chip select signal is held active at the end of a transfer until a control field with new data and control information is loaded into SPIDAT1." when it's set heigh. I wander how to deactivate the chip select signal after an transmission if i don't need to send new data.

Thanks,

Huang!

0 Rahul Prabhu over 13 years ago in reply to ____-__-__

TI__Guru** 116170 points

Huang,

You will find the information regarding controlling the polarity of SPI Chip select on the following wiki:

http://processors.wiki.ti.com/index.php/Using_SPI_Chip_Select_Pin_on_C674x/OMAP-L1x

Regards,

Rahul

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Question about OMAPL138 SPI