• State Resolved
  • Locked Locked
  • Replies 6 replies
  • Answers 1 answer
  • Subscribers 22 subscribers
  • Views 380 views
  • Users 0 members are here
Support feedback
Options
Options
Related

This thread has been locked.

If you have a related question, please click the "Ask a related question" button in the top right corner. The newly created question will be automatically linked to this question.

LMK04828: SYNC NOT WORKING PROPERLY

Yoel Ben-Naim
Prodigy 30 points
Part Number: LMK04828

Hi 

I have a problem with the SYNC operation which not always operate. Sometimes the sync operation works and I can see that the delays I entered take effect, but sometimes it looks as if nothing changed and that sync did not occur.

The SYNC I am using is internal in Continuous mode.

The values of the relating registers are.

REG 139 Value  03h

REG 140 Value  81h

REG 143 Value  10h

REG 144 Value FFh-------------- START SYNC ASSERTION

REG 144 Value 00h

REG 144 Value FFh-------------- STOPSYNC ASSERTION

Any thoughts? 

  • 0
    TI__Mastermind 20900 points

    Hello,

    can you please share a full register configuration that we can examine that further?

    Thanks

    Julian

  • 0
    TI__Genius 12560 points

    Hi Yoel,

    I would be assuming you are following the section 9.3.1 of LMK04828 datasheet for asserting the SYNC.

    For your setup examine, would be great, if you can share the used configuration or full register settings.

    Thanks!

    Regards,

    Ajeet Pal

  • 0 in reply to Ajeet Pal
    Prodigy 30 points

    Sure

    Register Value
    0 90
    0 10
    16e 3b
    100 7e
    101 88
    103 7
    104 22
    105 11
    106 e0
    107 1
    108 7e
    109 de
    10b 67
    10c 22
    10d 11
    10e e0
    10f 55
    110 7e
    111 88
    113 7
    114 22
    115 11
    116 e0
    117 60
    118 7e
    119 88
    11b 7
    11c 22
    11d 11
    11e e0
    11f 66
    120 7e
    121 88
    123 7
    124 22
    125 11
    126 e0
    127 66
    128 7e
    129 88
    12b 7
    12c 22
    12d 11
    12e e0
    12f 65
    130 7e
    131 56
    133 7
    134 22
    135 11
    136 e0
    137 55
    138 0
    139 3
    13e 3
    13f 0
    140 83
    141 0
    142 0
    143 11
    144 ff
    145 7f
    146 0
    147 f
    148 2
    149 42
    14a 0
    14b 16
    14c 0
    14d 0
    14e c0
    14f 7f
    150 3
    151 2
    152 0
    153 0
    15e 0
    15f 13
    162 44
    162 44
    171 aa
    172 2
    173 0
    17c 15
    17d 33
    166 0
    167 0
    169 59
    16a 20
    16b 0
    16c 0
    16d 0
    13a 0
    13b 1e
    13c 0
    13d 8
    153 0
    154 78
    155 0
    156 78
    157 0
    158 96
    160 0
    161 1
    165 c
    164 0
    163 0
    168 c
    167 0
    166 0
    183 1
    183 0
  • 0 in reply to Yoel Ben-Naim
    TI__Genius 12560 points

    Hi Yoel,

    I usually prefer to have TICS pro format config file to recheck on GUI. But anyways, I could manage with the available format data.

    While you are performing the SYNC, SYSREF_MUX set to 0 (Normal SYNC) and toggle the SYNC_POL along with 0x144 --> 00 to allow the sync signal to reset the divider circuit.

    So in your configuration, SYNC should be asserted (SYNC_POL toggle) as shown below:

    The values of the relating registers are.

    REG 139 Value  03h

    REG 140 Value  81h

    REG 143 Value  10h

    REG 144 Value FFh-------------- START SYNC ASSERTION

    REG 144 Value 00h   <--------   SYNC_POL toggle (SYNC insert)

    REG 144 Value FFh-------------- STOPSYNC ASSERTION

    Thanks!

    Regards,

    Ajeet Pal

  • 0 in reply to Ajeet Pal
    Prodigy 30 points

    Thank you Ajeet!

    This certainly clarifies some issues. 

    After sync is done, do I need to return SYSREF_MUX to  3 (CONTINUES MODE)?

  • 0 in reply to Yoel Ben-Naim
    TI__Genius 12560 points

    Hi Yoel,

    Yes, After sync operation, you can adjust the SYSREF_MUX to continuous or pulsar mode based on use case.

    Regards,

    Ajeet Pal