Renesas Hitachi H8S/2194 Series Hardware Manual page 650

(5) CTL Gain Control Register (CTLGR)
Bit : 7
—
1
Initial value :
—
R/W :
Sets the CTLFB switch in the CTL amplifier circuit to on/off and CTL amplifier gain.
CTLGR is an 8-bit read/write register. Bits 7 and 6 are reserved. No write in it is valid. If read
is attempted, an undetermined value is read out. It is initialized to H'C0 by a reset or stand-by.
Bit 7 to 6: Reserved
Reserved bits; writes are disabled. If read was attempted, an undetermined value is read out.
Bit 5: CTL Selection Bit (CTLE/
Controls whether the amplifier output or EXCTL is used as the CTLP signal supplied to the CTL
circuit.
Bit 5
 
CTLE/ Description
0 AMP output
1 EXCTL
Bit 4: SW Bit of the Feedback Section of CTL Amplifier (CTLFB)
Turning on/off the SW of the feedback section allows adjustment of gain.
See figure 28.4, CTL Input Circuit.
Bit 4
CTLFB Description
0 Turns off CTLFB SW
1 Turns on CTLFB SW
6 5 4
— CTLE/ CTLFB
1 0 0
—
R/W R/W
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)
3 2
CTLGR3 CTLGR2 CTLGR1
0 0
R/W R/W
Rev. 2.0, 11/00, page 623 of 1037
1 0
CTLGR0
0 0
R/W R/W
(Initial value)
(Initial value)