Bare Metal is not Debian?  If you use bare metal you need to set up all pin mux 
and initialize memory controller typically with a gel file in CCS.  Briefly 
looking at your code assuming nothing is interference with mux I'd make sure 
your SPI chipselect is properly timed with a scope if you're truly getting 
commands through.  Also a cheap Salae logic analyzer is very handy for what 
you're doing costs about  $200 

Sent from Yahoo Mail on Android 
 
  On Thu, May 12, 2016 at 9:12 AM, 
[email protected]<[email protected]> wrote:   Hello Gregor, 
I'm actually working on a project incolving a SPI connection between a 
BeagleBone black and an AD7606 (ADC). I have a couple of problems to enable 
properly the SPI connection, could you give me more details about how you have 
done it ? (if it worked).
I'm programming the BB_black in bare-metal, and it will communicate with the 
ADC using the SPI, so I really need to find out how to do it in order for my 
system to work.
Best regards,
Cedric.

Le dimanche 31 août 2014 14:03:31 UTC+2, Gregor Steiner a écrit :
Hi,

I want to use SPI through direct memory access on Debian, here is what I got so 
far:

int enableSPIClock()
{
    // map a pointer to the clock control block
    pClockControl = (char*)mmap(0, 4096, PROT_READ | PROT_WRITE, MAP_SHARED, 
memFd, SOC_CM_PER_REGS);

    HWREG(pClockControl + CM_PER_SPI1_CLKCTRL) |= CM_PER_SPI1_CLKCTRL_ 
MODULEMODE_ENABLE;
    while(CM_PER_SPI1_CLKCTRL_ MODULEMODE_ENABLE != (HWREG(pClockControl + 
CM_PER_SPI1_CLKCTRL) & CM_PER_SPI1_CLKCTRL_MODULEMODE ));
    
    return 0;
}

int enableSPI()
{
    enableSPIClock();
    
    McSPIReset(spi);
    McSPICSEnable(spi);
    McSPIMasterModeEnable(spi);
    
    // set D0 as output-MOSI , set D1 as input-MISO
    McSPIMasterModeConfig(spi, MCSPI_MULTI_CH, MCSPI_TX_RX_MODE, 
MCSPI_CH0CONF_DPE0_ENABLED | MCSPI_CH0CONF_DPE1_DISABLED, chNum);
    McSPIClkConfig(spi, 48000000, 6000000, chNum, MCSPI_CLK_MODE_0);
    McSPIWordLengthSet(spi, MCSPI_WORD_LENGTH(8), chNum);
    McSPICSPolarityConfig(spi, MCSPI_CS_POL_LOW, chNum); 
    McSPITxFIFOConfig(spi, MCSPI_TX_FIFO_ENABLE, chNum); 
    McSPIRxFIFOConfig(spi, MCSPI_RX_FIFO_ENABLE, chNum);
    
    return 0;
}

int spiWrite(uint8_t *tx, uint32_t length)
{
    // cs line is forced to low state.
    McSPICSAssert(spi, chNum);

    // enable the spi channel for communication.
    McSPIChannelEnable(spi, chNum);

    while (length > 0)
    {
        McSPITransmitData(spi, (unsigned int)(*tx++), chNum);
        length--;
        
        unsigned int rx = McSPIReceiveData(spi, chNum);
    }

    // force cs line to the inactive state.
    McSPICSDeAssert(spi, chNum);

    // Disable the spi channel.
    McSPIChannelDisable(spi, chNum);    
}

I'm writing to a DAC and every 2nd or 3rd message actually goes through (gets 
recognized by the DAC).

The StarterWare site http://processors.wiki.ti.com/ index.php/StarterWare_McSPI 
references the Interrupt and DMA mode, but I'm not sure if I should use them..?
If anyone has tried a similar thing I'd be more than happy to hear about it.



-- 
For more options, visit http://beagleboard.org/discuss
--- 
You received this message because you are subscribed to the Google Groups 
"BeagleBoard" group.
To unsubscribe from this group and stop receiving emails from it, send an email 
to [email protected].
To view this discussion on the web visit 
https://groups.google.com/d/msgid/beagleboard/b76f52ec-e5a5-49d9-b4cb-24cc56e3c03e%40googlegroups.com.
For more options, visit https://groups.google.com/d/optout.
  

-- 
For more options, visit http://beagleboard.org/discuss
--- 
You received this message because you are subscribed to the Google Groups 
"BeagleBoard" group.
To unsubscribe from this group and stop receiving emails from it, send an email 
to [email protected].
To view this discussion on the web visit 
https://groups.google.com/d/msgid/beagleboard/1321887198.1115319.1463062281351.JavaMail.yahoo%40mail.yahoo.com.
For more options, visit https://groups.google.com/d/optout.

Reply via email to