[OMAP-L137] Enable SPI setup/hold time

Andreas Weishaupt

Other Parts Discussed in Thread: OMAP-L137

Hi.

I need to adjust setup and hold times for SPI1 in master mode in 4-PIN CS mode. I can successfully see the signals on the scope, but I don't see any setup and hold time. I think it's something in the configuration again. Could you please help me?

Here's the conf:

    spiParams.spiHWCfgData.pinOpModes = Spi_PinOpMode_SPISCS_4PIN;
    spiParams.spiHWCfgData.configDatafmt[0].charLength   = 16;    /* 8bit Addr + 8bit Data */
    spiParams.spiHWCfgData.configDatafmt[0].clkHigh      = FALSE ;
    spiParams.spiHWCfgData.configDatafmt[0].lsbFirst     = FALSE;
    spiParams.spiHWCfgData.configDatafmt[0].oddParity    = FALSE;
    spiParams.spiHWCfgData.configDatafmt[0].parityEnable = FALSE ;
    spiParams.spiHWCfgData.configDatafmt[0].phaseIn      = TRUE ;
    spiParams.spiHWCfgData.configDatafmt[0].waitEnable   = TRUE;
    spiParams.spiHWCfgData.configDatafmt[0].wDelay       = 2;
    spiParams.spiHWCfgData.delay.c2TDelay = 3;
    spiParams.spiHWCfgData.delay.t2CDelay = 3;
    spiParams.spiHWCfgData.waitDelay = 2;
    spiParams.spiHWCfgData.intrLevel     = TRUE;

And this is before I send:

dataparam.flags = 0x00;
dataparam.chipSelect = 0x01;

Thank you for your help.

Andreas

over 15 years ago

0 tlee over 15 years ago

TI__Guru 62975 points

Andreas,

Which device and OS are you using?

-Tommy

0 Gus Martinez over 15 years ago in reply to tlee

TI__Mastermind 29071 points

Can you also clarify what you mean by setup and hold time? Are you talking about setup and hold of the data around the clock? Or are you referring to the CS pins somehow?

0 jc-ti over 15 years ago

TI__Mastermind 27585 points

If you are using CCS, I would check the SPIDELAY register (48h) before and after you do the config to verify that the delay numbers are actually increasing when you set them.

Jeff

0 Andreas Weishaupt over 15 years ago in reply to jc-ti

Expert 1270 points

Hi all and thanks for your answers. First my system: OMAP-L137 EVM only using the C6747, BIOS version 5.33.01, PSP drivers 1.20.
I mean adjusting the 4 following timings:

- t_CS-CLK: time from CS enable to CLK at begin of transfer

- t_CS-DATA: time from CS enable to SOMI at begin of transfer

- t_CLK-CS: time from CLK to CS disable at end of transfer

- t_DATA-CS: time from SOMI to CS disable at end of transfer

In the SPI User Guide, the t_C2TDELAY and t_T2CDELAY (page 49) are exactly what I mean by t_CS-CLK and t_CLK-CS .

Finally, I've checked the SPIDELAY register and it looks fine - i.e. my settings are well reflected. But I still don't see t_C2TDELAY and t_T2CDELAY. What am I missing?

0 Gus Martinez over 15 years ago in reply to Andreas Weishaupt

TI__Mastermind 29071 points

See this wiki article. It should help you understand this delay feature better.

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

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[OMAP-L137] Enable SPI setup/hold time