(ADV7182A)What are these scripts doing?

Hi Kawa-San,

Please find the below inline comments,

 Q1) 0x52 is hidden register.
        Why we need these script?

These writes are normally determined during characterization of the part and we typically do not release any detail on them unfortunately.

Q2) 0x9C is read only.
       Why we need to write this?

   The Reset Current Clamp Circuitry writes be performed each time the INSEL register is written to. This will speed up the lock time of the ADV7182.

Q3) I couldn't find information for these two.
42 0E 00 ; Enter User Sub Map 
42 13 00 ; Enable ADV7182A for 28_63636MHz crystal
What are these two doing?

    As per expert comment "ADV7182 datasheet states that register 0x13 is a read only register (status register 3). Actually two registers share the register address 0x13.

When you read from register 0x13, you read back the Status Register 3 data ( this is read only) . When you write to register 0x13 you write to an internal control register. The internal control register is write only and contains the XTAL_TTL_SEL bit ".

Please refer here (+) How Do I Use An External Oscillator to Clock the ADV7182 ? - Q&A - Video - EngineerZone (analog.com)

Thanks,

Poornima

Hi Kawa-San,

Please find the below inline comments,

 Q1) 0x52 is hidden register.
        Why we need these script?

These writes are normally determined during characterization of the part and we typically do not release any detail on them unfortunately.

Q2) 0x9C is read only.
       Why we need to write this?

   The Reset Current Clamp Circuitry writes be performed each time the INSEL register is written to. This will speed up the lock time of the ADV7182.

Q3) I couldn't find information for these two.
42 0E 00 ; Enter User Sub Map 
42 13 00 ; Enable ADV7182A for 28_63636MHz crystal
What are these two doing?

    As per expert comment "ADV7182 datasheet states that register 0x13 is a read only register (status register 3). Actually two registers share the register address 0x13.

When you read from register 0x13, you read back the Status Register 3 data ( this is read only) . When you write to register 0x13 you write to an internal control register. The internal control register is write only and contains the XTAL_TTL_SEL bit ".

Please refer here (+) How Do I Use An External Oscillator to Clock the ADV7182 ? - Q&A - Video - EngineerZone (analog.com)

Thanks,

Poornima

Hi 

Thank you for your reply.

I understood

Best regards

Kawa