Other Parts Discussed in Thread: LMK04828, CODELOADER
I have another problem with the LMK04828.
There is a control called “SYNC_DISSYSREF” located at bit 7, register 0x144.
I cannot not set that bit to logic 1. It always resets itself back to 0.
I am controlling that bit as part of the calibration sequence given in the data sheet pages 37-38 (see steps 2 and 3), but it doesn’t matter because I have not been able to set it under any condition.
In the procedure register 0x144 must be set to x00 during the clock alignment cal, and then set back to xFF to avoid an unintentional cal.
If I write data = xFF, the register reads back x00
If I write data= x80, it returns x00
If I write data x7F, it returns x7F
So not only doesn’t bit 7 set, when forced high it causes the other 6 bits to reset to 0.
If the device is powered on, and I write only to this register the bit still cannot be controlled. I have not found a configuration that allows bit 7 to be set.
I have also tried this on multiple devices with the same results.
Can you give some guidance as to what is wrong?
