Get Frames from ADNS-9800

Projects Programming
1

Hello,
I want to get Pixels array from ADNS-9800. It's Datasheet says this:

Procedure of Frame Capture:

  1. Reset the chip by writing 0x5a to Power_Up_Reset register (address 0x3a).
  2. Enable laser by setting Forced_Disable bit (Bit-0) of LASER_CTRL) register to 0.
  3. Write 0x93 to Frame_Capture register.
  4. Write 0xc5 to Frame_Capture register.
  5. Wait for two frames.
  6. Check for first pixel by reading bit zero of Motion register. If = 1, first pixel is available.
  7. Continue read from Pixel_Burst register until all 900 pixels are transferred.
  8. Continue step 3-7 to capture another frame

Here's What I did:

  # define REG_Motion                               0x02
    # define REG_Pixel_Burst                          0x64
    # define REG_Frame_Capture                        0x12
    ...................
    void setup()
    {
        //Initialization (Uploading Firmware and First two steps from Procedure of Frame Capture)
        ....
    }
    void loop()
    {
      adns_write_reg(REG_Frame_Capture, 0x93);
      delay(1);
      adns_write_reg(REG_Frame_Capture, 0xc5);
      delay(2);
      byte check_Motion_register = adns_read_reg(REG_Motion);
      
      //Display Motion Register in serial monitor
      Serial.println(check_Motion_register);
      
      if(check_Motion_register == 1)
      {
         for(int i = 1; i <= 900; i++)
         {
              Serial.println(adns_read_reg(REG_Pixel_Burst));
              delay(1);
         }
      }
      
      delay(100);
    }

But I have problems when I try to do this: When I look at Serial monitor I see that 'check_Motion_register' is always 32 or 160 and sometimes 0 but never 1 but datasheet says that it must be 1 if first pixel is ready. What am I doing wrong? How to fix this?

(NOTE: Circuit and initialization code is correct (Because it reads Delta_X and Delta_Y registers without any problem))

Datasheet: http://datasheet.octopart.com/ADNS-9800-Avago-datasheet-10666463.pdf (Page: 18-19)

thanks

2
  1. Check for first pixel by reading bit zero of Motion register. If = 1, first pixel is available.

Check bit zero.

That is not the same as checking that the whole byte has the value 1.

3

thanks for replying @michinyon but How to do this?
I have changed: 'adns_read_reg(REG_Motion)' to this:

  digitalWrite(ncs, LOW);
  SPI.transfer(0x02);
  delay(1);
  byte check_Motion_Register = SPI.transfer(0);
  delay(1);
  digitalWrite(ncs, HIGH);

check_Motion_Register |= B00000001;  

  Serial.println("------------");
  Serial.println(check_Motion_Register);
  Serial.println("------------");

and how to read all pixels ? is code for reading pixels correct?

thanks

4

So I have fixed my code for reading Motion Register's byte 0:

# define REG_Motion                               0x02
    # define REG_Pixel_Burst                          0x64
    # define REG_Frame_Capture                        0x12
    ...................
    void setup()
    {
        //Initialization (Uploading Firmware and First two steps from Procedure of Frame Capture)
        ....
    }
    void loop()
    {
      adns_write_reg(REG_Frame_Capture, 0x93);
      delay(1);
      adns_write_reg(REG_Frame_Capture, 0xc5);
      delay(2);
      byte check_Motion_register = adns_read_reg(REG_Motion);
      check_Motion_register |= B00000001;      

      //Display Motion Register in serial monitor
      Serial.println(check_Motion_register);
      
      if(check_Motion_register == 1)
      {
         for(int i = 1; i <= 900; i++)
         {
              Serial.println(adns_read_reg(REG_Pixel_Burst));
              delay(1);
         }
      }
      
      delay(100);
    }

But I have one problem. In Serial Monitor Pixel_Burst register return's all pixels as zeros. Datasheet says this:

  1. Continue read from Pixel_Burst register until all 900 pixels are transferred.

and In code I'm using this:

if(check_Motion_register == 1)
      {
         for(int i = 1; i <= 900; i++)
         {
              Serial.println(adns_read_reg(REG_Pixel_Burst));
              delay(1);
         }
}

what am I doing wrong? How to fix this?

5

Did you ever figure out how to read the frames from this sensor? I'm trying to do the same thing and running into the same issue as you. I've tried a bunch of combinations of reading these registers according to the data sheet but it does not seem to return the correct data.

Thanks!

6

adns_read_reg() function calls digitalWrite(ncs, HIGH) which automatically exits burst mode.

So you'd better not use adns_read_reg() function for reading REG_Motion or REG_Pixel_Burst during burst mode.

Wish you good luck!