DM648 I2C PSP Driver

dchasse

I am trying to get i2c running on a DM648 running at 1100MHZ using the i2c PSP driver included with the dvsdk 1.11.0.0 version. The PSP driver version included is 1.10.00. The driver works fine running at 864MHZ but when we upgraded our design to use 1100MHZ processor the board hangs on a SYS_abort due to the i2c driver. The module that fails is ddc_i2c.c at line 154. Since we are running at 1100MHZ, SYSCLK3 is 1100MHZ/6 or 183.3MHZ which exceeds the DDC_I2C_MAX_INPUT_FREQ limit which is defined as 150MHZ.

Question: Is there a later version of PSP driver that will allow using the 1100MHZ part. If not can I safely change the upper limit to work with the faster DSP?

over 12 years ago

0 David Friedland over 12 years ago

TI__Mastermind 18320 points

The PSP team doesn't seem to have any suggestions on this issue and your problem actually seems to be rooted in the system/device rather than the the PSP software. For that reason, I have moved this thread over to the DM64x forum in hopes that it will get a faster response there.

Dave

0 dchasse over 12 years ago in reply to David Friedland

Prodigy 90 points

Has the PSP team verified that the i2c driver will work on a DM648 running at 1100MHZ?

0 Renjith Thomas over 12 years ago in reply to dchasse

Guru 31670 points

What is that you are trying to achieve by running I2C controller at 1100 MHz? What is the final I2C SCL clock frequency that you need? 100/400 KHz or more? What are the I2C peripherals that you have connected to the bus?

0 dchasse over 12 years ago in reply to Renjith Thomas

Prodigy 90 points

Let me be clear, I am not running the I2C bus at 100MHZ. The DM648 is running at 1100MHZ. The final I2C clock is 400KHZ. The driver takes the SYSCLK3 value of 1100MHZ/6 or 183.33MHZ and should create a prescaler and divisor to get to I2C frequency of 400KHZ. However if the input frequency(SYSCLK3) is larger than 150MHZ the driver generates an error.

The devices I am communicating on the I2C bus are AD5311, PCA9547, ISL76683, MCP3021, MAX1606, AD5383 and CAT34TS02. All devices will be run at 400KHZ.

0 Renjith Thomas over 12 years ago in reply to dchasse

Guru 31670 points

If you drive the SYSCLK3 at less than 150KHz and change I2C controller Clock Divider Registers accordingly, you'll be able to achieve 400KHz. Have you tried this?

0 dchasse over 12 years ago in reply to Renjith Thomas

Prodigy 90 points

Yes I did and it works okay. This was done on a previous revision of the board where we ran the DSP at 864MHz. This generated a SYSCLK3 of 864/6 or 144MHz. The I2C driver was okay since the input frequency to the I2C was less than 150MHz a limit defined in the driver.

I rebuilt the I2C driver to increase the upper limit of the I2C input clock to be greater than 1100MHz/6 or 183.33MHz and it does now seem to work for a final I2C frequency of 400KHz.

I guess I am looking for confirmation that this change to the PSP I2C driver was okay.

0 Renjith Thomas over 12 years ago in reply to dchasse

Guru 31670 points

So, can I assume that this issue is resolved?

0 dchasse over 12 years ago in reply to Renjith Thomas

Prodigy 90 points

I would like confirmation that the change I made to the PSP I2C driver was correct. The newly built driver does seem to work. I am just surprised that the 1100MHz DM648 was not supported.

You can consider the issue resolved.

0 Renjith Thomas over 12 years ago in reply to dchasse

Guru 31670 points

Can you mark this post as answered and close it?

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DM648 I2C PSP Driver