Rainbow Electronics RF22 - Manual (Page 67)

RF22
Version: 0.1 Date: 12/23/2008
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Register 21h. Clock Recovery Offset 2
Bit D7 D6 D5 D4 D3 D2 D1 D0
Name rxosr[10:8] stallctrl ncoff[19:16]
Type R/W R/W R/W
Reset value = 00000001
Bit Name Function
7:5 rxosr[10:8] Oversampling Rate. Upper bits.
4 stallctrl Used for BCR Purposes.
3:0 ncoff[19:16] NCO Offset. See formula above.
Register 22h. Clock Recovery Offset 1
Bit D7 D6 D5 D4 D3 D2 D1 D0
Name ncoff[15:8]
Type R/W
Reset value = 01000111
Bit Name Function
7:0 ncoff[15:8] NCO Offset.
See formula above
Register 23h. Clock Recovery Offset 0
Bit D7 D6 D5 D4 D3 D2 D1 D0
Name ncoff[7:0]
Type R/W
Reset value = 10101110
Bit Name Function
7:0 ncoff[7:0] NCO Offset.
See formula above
The loop gain can be calculated as crgain = 2 16 / (rxosr x h x P), where the modulation index h = 2 x FD / RX_DR.
Register 24h. Clock Recovery Timing Loop Gain 1
Bit D7 D6 D5 D4 D3 D2 D1 D0
Name Reserved crgain[10:8]
Type R/W R/W
Reset value = 00000010
Bit Name Function
7:3 Reserved Reserved.
2:0 crgain[10:8] Clock Recovery Timing Loop Gain.
Register 25h. Clock Recovery Timing Loop Gain 0
Bit D7 D6 D5 D4 D3 D2 D1 D0
Name crgain[7:0]
Type R/W
Reset value = 10001111
Bit Name Function
7:0 crgain[7:0] Clock Recovery Timing Loop Gain.