spidev_test in l138

Francis Wong

Other Parts Discussed in Thread: OMAPL138

Hi,

I have successfully loaded and initiated the spidev module into my l138 board.

However, when I try to execute the spidev_test, the output is always

./a.out -D /dev/spidev1.0
spi mode: 0
bits per word: 8
max speed: 500000 Hz (500 KHz)

FF FF FF FF FF FF
FF FF FF FF FF FF
FF FF FF FF FF FF
FF FF FF FF FF FF
FF FF FF FF FF FF
FF FF FF FF FF FF
FF FF

I have checked the source code of spidev_test.c the output should be something close to

                0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF,
                0x40, 0x00, 0x00, 0x00, 0x00, 0x95,
                0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF,
                0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF,
                0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF,
                0xDE, 0xAD, 0xBE, 0xEF, 0xBA, 0xAD,
                0xF0, 0x0D,

Which step am I missing?

thanks

Francis

over 14 years ago

0 tlee over 14 years ago

TI__Guru 62975 points

Francis,

What is your development environment? Linux? BIOS? CSL?

-Tommy

0 Francis Wong over 14 years ago in reply to tlee

Prodigy 85 points

Hi Tommy,

I am developing under Linux

thanks

Francis

0 tlee over 14 years ago

TI__Guru 62975 points

Are you configuring SPI for internal loopback or do you have an external setup?

0 Francis Wong over 14 years ago in reply to tlee

Prodigy 85 points

Hi,

I have tried to connect the MISO and MOSI together

Or specify the -l option in the spidev_test

Both of them have failed. Is this a bad idea to connect the MISO and MOSI?

I am really new into the SPI driver, sorry for my "stupid" questions.

Francis

0 tlee over 14 years ago in reply to Francis Wong

TI__Guru 62975 points

Are you using the standard L138 EVM baseboard? Which SPI are you using?

0 Francis Wong over 14 years ago in reply to tlee

Prodigy 85 points

Hi tlee,

Yes, you are right. I am using the standard L138 EVM board and trying to run the spidev_test loop back test.

I have edited the board-da850-evm.c to load the spidev and used scope to verify there is output. However, the loop back test never works for me.

thanks

Francis

0 Pradeep TR over 14 years ago in reply to Francis Wong

Prodigy 235 points

Hi Francis,

Am facing this issue now when tried to make the loopback work in the TI8148 board with

PSP version TI814X-LINUX-PSP-04.01.00.03.

Were you able to get it right? if yes what was the missing thing in the set-up.

Thanks in advance.

-P

0 Pradeep TR over 14 years ago in reply to Francis Wong

Prodigy 235 points

hi,

hope the way to use it is #./spidev_test -D /dev/spidev1.0 -l ,this "-l" was missing I beleive ,but for me even after giving it am getting just "ff ff " am making use of the

same bus number and chip select to which we have connected the spi falsh, and have set the EVM boadr settings in the SPI boot mode and in the SPI/NAND switch has set it to SPI.

Can this be cause of the issue or the max speed_hz which myself have set it to 6MHz?

Does the TI8148 support the loopback mode for "1.0"bus num.chip select?

-P

0 anisha kumawat over 12 years ago in reply to Francis Wong

Prodigy 20 points

Hi am working on omapl138, even i have started working for spi loopback, can you please help me in what all changes you did in board-da850-evm.c to load spidev, did your mux.h had spi configurations already? please help me

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spidev_test in l138