DS90UB947-Q1: question about DS90UB947-Q1

Hi Jimmy,

Allow me to take a further look into the details of INTB failing to clear for the 947 and 948 before determining if alternative clearing methods exist.

Jimmy Huang said:

After the interrupt is triggered, it needs to read 0xc7 to clear the interrupt

As of right now, this is the known method of resetting the interrupt. This is confirmed through both datasheets as the only identified method;

According to the serializer datasheet, the DS90UB947-Q1:

"External controller detects INTB = LOW; to determine interrupt source, read ISR register."

"A read to ISR will clear the interrupt at the Serializer, releasing INTB"

According to the deserializer datasheet, the DS90UB948-Q1:

"External controller detects INTB = LOW; to determine interrupt source, read ISR register."

"A read to ISR clears the interrupt at the Serializer, releasing INTB"

Jimmy Huang said:

Is there any other way or method to automatically clear it?

We can look into this if the primary method of clearing is still unsuccessful.

Jimmy Huang said:

frequent triggering sometimes fails to clear the interrupt of the intb pin after reading 0xc7

Would you mind sharing further details about the test cases?

What is the order of events? I'm assuming-

1. INTB_IN triggered >

2. Read 0xC7 over I2C on 947 device >

3. Repeat

Until the INTB fails to clear on the Serializer (947). When it fails to clear, is it stuck in this state?

Jimmy Huang said:

feedback of the i2c reading result is also successful.

To clarify, does this mean reading 0xC7 results in a successful read of the INTB indicated on the Serializer device?

Best,

Miguel