DS1077 IC output 0 fault

[See_Mos]

Has anyone done anything with the Analog Devices DS1077, in my case a DS1077Z-100

I have output 1 working OK but cannot get 12.5MHz and 100MHz from output 0.  25MHz and 50MHz are OK.

These are the test values that I am using:-

Code Select Expand

' test MUX high byte
'    Dim MUX_High As Byte = %00011000    ' $18 output = 0MHz ?? should be 100MHz
'    Dim MUX_High As Byte = %00011010    ' $1A output = 50MHz
'    Dim MUX_High As byte = %00011100    ' $1C output = 25MHz   
    Dim MUX_High As Byte = %00011110    ' $1E output = 25MHz ?? should be 12.5MHz   
       
    I2COut SDA,SCL,$B0,[$02,MUX_High,$0]

Bits 1 and 2 control the prescaler.  MUX_Low is not used for output 0 so just cleared.

The tolerance is not very good so it is just a challenge to make it work.

[midali]

Try with 32 or 34 in decimal :
Dim MUX_High As Byte = %00100000    ' $20 = 32 in decimal

If doesn't work, I suggest to make a simple test :

Code Select Expand

Dim MUX_High As Byte
For MUX_High = 32 To 40 ' Test values: 32, 33, 34, 35, 36, 37, 38, 39, 40
    I2COut SDA, SCL, $B0, [$02, MUX_High, $0]
    DelayMs 1000
Next

[See_Mos]

OK, that was a silly mistake, I should have written Dallas.  I was getting frustrated and confused.  I had also been working on Analog Devices AD9833 and AD9850.