DIX4192 Current Address Read format

Hi Machida,

When reading a single byte over I2C, you must send the address of the device you want to read from first, then the register within that device you want to read from. The slave device will then respond with the data in that register. The DIX4192 data sheet Figure 20 is correct.

Justin

Hi Justin-san,

I'm sorry, I'm not sure why you mentioned "DIX4192 data sheet Figure 20 is correct".

According to datasheet of DIX 4192, there is following description.

The current address read operation of Figure 20(a) assumes the value of the register address from the previously executed write or read
operation, and is useful for polling a register address for status changes.

I believe that this means that user do NOT need to set "register address" due to previous register address will be used.
So, I could not understand why user should set "register address" in this operation(Figure 20(a)).

In this operation(Figure 20(a)), after sending slave address of the device w/ Read flag, I believe that "Register data" should be sent from slave device.

Best Regards,
Machida

Hi Machida,

Sorry I misunderstood the first time I looked at it. This does seem confusing and unfortunately I do not have a reliable way of testing this at the moment. The TAS1020B interface will only do reads in style B. I plan to get an MSP430 in a state where i can test this kind of read. I will update you when I am able to test this.

Justin

Justin-san,

Is there any update ?

Best Regards,
Machida

Hi Machida-san,

This past weekend was a US holiday, and I was out of town. I just returned today and plan to test this by the end of the week.

Justin

Hi Machida-san,

I have ran some tests with a launchpad and I agree that the figure should be changed to reflect what you have shown in your origional post. When you perform a read request without a write for register address, it will return the value of the last register read or wrote to. This means figure 20(a) should be slave address sent from master to salve, then register contents sent from slave to master. We are planning to update the data sheet for the DIX4192 in the near future and will make this change. Thank you for pointing this out to us.

Justin

Hi Justin-san,

Sorry to go back previos thread.
i want to know when you will release datasheet which is included fixed figure 20(a).
Can you answer ?

Best Regards,
Machida

Hi Machida,

We plan on releasing the revised DIX4192 data sheet in December.

Justin