2000 Mar 21
57
Philips Semiconductors
Preliminary specification
Channel encoder/decoder CDR60
SAA7392
7.16.3
EFM C
LOCK
C
ONFIGURATION
R
EGISTER
3 (EFMC
LOCK
C
ONF
3)
This is a dual-function register, the specific function is controlled by the state of bit 7.
The integrator of the PI controller can be preset by writing to this register with the MSB set to logic 0. The value written
is interpreted as a signed value. The current integrator value can be read back via this register.
To program the K
p
and K
i
values, bit 7 of the EFMClockConf3 register must be logic 1.
To determine the time constant of the I-branch, the sample frequency of the integrator must be known. This sample
frequency is programmed via register EFMClockConf4 when the MSB is logic 1. The LSB is actually the switch to turn
off the integrator path. The value in the integrator is not affected by programming this bit, so the integrator can be used
as offset when Ki is logic 0.
Table 129
EFM Clock Configuration Register 3 (address 36H) - READ/WRITE
Table 130
Selection of coefficient K
p
Table 131
Selection of the coefficient K
i
7
6
5
4
3
2
1
0
0
1
IntegVal.6
Kp.2
IntegVal.5
Kp.1
IntegVal.4
Kp.0
IntegVal.3
Ki.3
IntegVal.2
Ki.2
IntegVal.1
Ki.1
IntegVal.0
Ki.0
Kp.2
Kp.1
Kp.0
COEFFICIENT K
p
0
0
0
0
1
0
0
1
1
0
0
1
0
1
0
4
2
1
0.5
0.25
Ki.3
Ki.2
Ki.1
Ki.0
COEFFICIENT K
i
0
0
0
0
0
1
1
1
1
0
0
0
1
1
0
0
1
1
0
0
1
0
1
0
1
0
1
0
1
1
1
1
1
1
1
1
0
1
0.5
0.25
0.125
0.0625
0.03125
0.015625
0.0078125