Hi all,
I meet a very strange problem when I program the CDCE62005 through SPI interface.
1. Firstly, in my FPGA code I write these vaules into the CDCE62005 and excute the RAM-to-EEPROM operation. The write commands are blew,
E9840320
69840301
E9020302
E9840303
69860314
101C0BE5
FD0037F7
00000001F //excute the RAM-to-EEPROM operation
2. After I proram these vaules into the CDCE62005 in order, I power down the CDCE62005 and then power up it again.
Then I write the READ command into the CDCE62005, like
0000000E //read register0
0000002E //read register1
0000004E //read register2
0000006E //read register3
0000008E //read register4
000000AE //read register5
000000CE //read register6
000000EE //read register7
I can get the return values from register1~7 correctly equal to the vaules I write into the EEPROM in the above operation.
But the problem is that the read back vaule from register0 is 00000000, rather than E9840320 which I write into the EEPROM.
This is a very strange problem. Why the operations of the register1~7 are correct but the register0 not??
And I find that if I want to read the register3, I must write the 0000006E command to the cdce62005, rather than 0000003E. It's different from the description of the datasheet.Could any one tell me why?