AD2S1210 set Encoder resolution!

Hi ttk84 ,

       I wanted to understand your current set up. In your set up, what is the setting of D2 and D3? You mentioned that is only 10-bit encoder, how many pulses are there in 1 revolution? As discussed in the Incremental encoder section of the datasheet, a 12bit resolution will have 1024 pulses in A and B. A lead B by 90degrees. Each A and B cycles will have 4 counts. 1024 pulses will have 4096 counts which is a 12-bit resolution. 

Regards,

Jonathan

Hi ttk84 ,

       I wanted to understand your current set up. In your set up, what is the setting of D2 and D3? You mentioned that is only 10-bit encoder, how many pulses are there in 1 revolution? As discussed in the Incremental encoder section of the datasheet, a 12bit resolution will have 1024 pulses in A and B. A lead B by 90degrees. Each A and B cycles will have 4 counts. 1024 pulses will have 4096 counts which is a 12-bit resolution. 

Regards,

Jonathan

Thank for your reply!

I have encoder reader. I understand you want to talk: 10 bit- A cycles =256ppr, 12bit- A cycles =1024...

When i set Res0=1, Res1=1, then Position data that I read is exactly 16 bits. 

But i change D2 and D3, then the value of A cycles  remains constant 256ppr, it doesn't change

I understand  when The Control Register (0x92) is set (Res0=1, Res1=1):

- 0x70:  A cycles = 256ppr

- 0x78:  A cycles = 1.024ppr

- 0x74:  A cycles = 4.096ppr

- 0x7C:  A cycles = 16.384ppr

Are there any other settings that affect the Encoder output?

Hi ttk84 ,

         Was the AD2S1210 in Configuration mode, A0=1 and A1=1? At power up the default value of control register (this is where encoder and RDC resolution are set) is 0x7E. Are you able to read the control register with this value?

Regards,

Jonathan

If  A0=1 and A1=1, when i power up, control register=0x00

i checked the write function again, i just write the value into the A register to change the EXC transmit frequency.