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CDCI6214: Question of Configuration

Part Number: CDCI6214

l have three questions now.

Q1:About he working mode of CDCI6214, when EEPROMSEL and REFSEL are tristated,the chip is on the fall back mode .What lknow about it is that on this mode , we can program the chip by i2c. However,What l do not know is that, on this mode,can this chip work with the output signal which we want? To speak another way, is tis mode specially used just for programming by serial i2c interface? or it can be also used for normal operating conditions ? which means we can get the output signal with the frequency we want(P.S.:What l understand is that the chip has two conditions : programing condition and normal operating condithion mentioned above.)

lf it can be also used for nomal operating conditons, then, on this mode, is eeprom used? And , on this mode,what is the ref input signal?  As l Know, REFSEL high and REFSEL low both indicate one kind of ref input signal.So, on this mode ,what about the ref input signal?

Q2: Our initialization and configuration procedure is:

(1): set REFSEL and EEPROMSEL MID(get rid of the pull down resistor) , power on , reset delay release.

(2): program the register(not eeprom) from 0x44 to 0x00(ignore some registers,all bits of which are reserved)

(3):accordng to the datasheet,we do the following point 2 to point 8(highlighted in the following picture)

(4) power dowm , set RESEL and EPROMSEL low(use the pul down resistor), power on , we think it should work on the normal operating condition.

l want to ask : is our procedure correct?

Q3:When it is on the fall back mode, we pocgram all the registers we need to conigure(I can successfully readback the value l have written into the register), and unok the eeprom and start the commit operation according to the point 4 and point 5, after doing this, we force a crc update, and then readback crc, but by internal ila of FPGA,l see the read back crc value contains 0x0000 all the time, what is the problem?

  • Hi Haitong,

    I will get back to you later today.


    Regards,

    Jennifer

  • Hi Haitong,

    1. "can this chip work with the output signal which we want?"
      1. What is the output frequency you want?
    2. "To speak another way, is tis mode specially used just for programming by serial i2c interface? or it can be also used for normal operating conditions ?"
      1. No, Fallback mode is not meant to be I2C only. Mode 0 also supports I2C programming.
      2. Yes, Fallback mode can be used for normal operating conditions. 
      3. This is what happens at Fallback:
        1. Step 1: REFSEL and EEPROMSEL are tristated
        2. Step 2: Power cycle
        3. Step 3: Default (fallback) config is loaded from EEPROM to active registers at power up
        4. Step 4: Device has finished start-up. Normal operation ensues. I2C programming can begin.
    3. "lf it can be also used for nomal operating conditons, then, on this mode, is eeprom used?"
      1. Yes, EEPROM is used. At power-up, the EEPROM settings that get loaded to the active registers are those listed in Table 13.
    4. "And , on this mode,what is the ref input signal? "
      1. In fallback, the expected REF input frequency is 25 MHz and the expected crystal frequency is 25 MHz. 
      2. Note this can be viewed using our TICSPRO GUI.
    5. "As l Know, REFSEL high and REFSEL low both indicate one kind of ref input signal.So, on this mode ,what about the ref input signal?"
      1. In Fallback mode, the REFSEL mode is set to PIN selection not register and chooses XTAL input by default when REFSEL is tristated.
    6. "l want to ask : is our procedure correct?"
      1. Looks good to me.
    7. "When it is on the fall back mode, we pocgram all the registers we need to conigure(I can successfully readback the value l have written into the register), and unok the eeprom and start the commit operation according to the point 4 and point 5, after doing this, we force a crc update, and then readback crc, but by internal ila of FPGA,l see the read back crc value contains 0x0000 all the time, what is the problem?"
      1. With your procedure, did the EEPROM page0/1 get written as intended and are loaded as expected on next power-up?

    Regards,

    Jennifer

  • Hi Jennifer! Thanks for reply! And your suggestion helps me a lot!
    I have soved my configuration peoblem, which means I can make the data stored in eeprom what I want. Of cource successfully loaded in all the registers on the normal operation mode. However, the output signal remains 291MHZ, but I want it to be 240MHZ. I can't understand. The only thing I can think is that our register value is not correct.

    What I need is: 20MHZ LVCOMS XIN input signal  ,  4 channels 240MHZ LVPECL output signal
    My register value is:
    R70 0x00460000
    R69 0x00450000
    R68 0x00440000
    R67 0x00430000
    R66 0x00420000
    R65 0x00410000
    R64 0x00400000
    R63 0x003F0000
    R62 0x003E0018
    R61 0x003D1500
    R60 0x003C0018
    R59 0x003B1060
    R58 0x003A0000
    R57 0x00390000
    R56 0x00380411
    R55 0x00370002
    R54 0x00360000
    R53 0x00350000
    R52 0x00340000
    R51 0x00330000
    R50 0x00320431
    R49 0x00310002
    R48 0x00300000
    R47 0x002F0000
    R46 0x002E0000
    R45 0x002D0000
    R44 0x002C0431
    R43 0x002B0002
    R42 0x002A0000
    R41 0x00290000
    R40 0x00280000
    R39 0x00270000
    R38 0x00260411
    R37 0x00250002
    R36 0x00240000
    R35 0x00230000
    R34 0x00220000
    R33 0x00210004
    R32 0x00200000
    R31 0x001F1E52
    R30 0x001E01A1
    R29 0x001D000F
    R28 0x001C0000
    R27 0x001B0000
    R26 0x001A0E00
    R25 0x00190000
    R24 0x00180000
    R23 0x00170000
    R22 0x00160000
    R21 0x00150000
    R20 0x00140000
    R19 0x00130000
    R18 0x00120000
    R17 0x00110000
    R16 0x00100000
    R15 0x000FA000
    R14 0x000E0000
    R13 0x000D003F
    R12 0x000C0000
    R11 0x000B0000
    R10 0x000A0000
    R9 0x00090000
    R8 0x00080000
    R7 0x00070000
    R6 0x00060000
    R5 0x00050020
    R4 0x00040000
    R3 0x00030000
    R2 0x00020005
    R1 0x00010020
    R0 0x00009000
    Please help me find what the problem is!

  • We use the TICS Pro , configuration is as follow:

  • Hi Haitong,

    Glad to hear the responses have helped you. Can you please share the .tcs configuration file instead? This will make it easier for me to check your problem.

    Regards,
    Jennifer