Sharp FO-77 Service Manual page 57

[Signals for status recognition according to input signals]
Signal Name
H:The handset is in the on-hook state.
RHS
L: The handset is in the off-hook state.
CI Incoming call (CI) detection signal
[Other signals]
Signal Name
TEL IN Receiving signal from line or modem
TEL OUT Transfer signal to line
SPOUT Speaker output signal
Transmission (DTMF) analog signal output
TXOUT
from modem
Reception (DTMF, others) analog signal input
RXIN
into modem
(Example: TEL speaking)
L1
CML
M
C
L2
B
CI
HANDSET
RX
TX
BIT7 BIT6 BIT5 BIT4
DAC
MIC GAIN L/O E SPKR E
IACR1
GAIN
LINEOUT
TXRX
IACR2
LOOP ATTENUATION
IACR3
Function
Function
TEL/LIU PWB CONTROL PWB
TXOUT
RXIN
TELIN
TELMUTE
TELOUT
SPEAKER
BIT3 BIT2 BIT1 BIT0
ADC
L/I E MIC E
GAIN
MICBIAS
RXTXLOOP
SEL
LINE SEL
NO Signal Name (CNLIUA)
1
2
3 TELMUTE
4
5
6
SP OUT
ENABLE
SPKRP-P
SP
DRIVER
MIC
GAIN
MICP
0,20,25,30dB
LINEIN
RCV VOL
LINE
DRIVER
LINEOUT
MUTE,0,
LINEOUT
–6,–12dB
ENABLE
TEL SPEAKING:
SPMUTE
FAX SENDING/RECEIVING:
Fig. 7
5 – 11
NO Signal Name (CNLIUA)
TELOUT 7
8
TELIN
9
CI 10
11
HS
12
RHS
RTLOOP
(0:1)
MIC ENABLE
(1:0)
(0:0)
(1:1)
DAC GAIN
0,6dB
MIC
ENABLE
1
MIC IN
LPF 0
LINE IN
ENABLE
ADC GAIN
1
LINE IN
0,–4dB
LPF 0
LNINSEL
MODEM
(0:0)
FM209
(1:1)
(1:0)
BZOUT
CML
SPMUTE
RCVOL
VTHON
FO-77U
UX-66U
RXIN
TXOUT
CML
+5V
DG
+24V
SIN
DAC
SOUT
ADC
RHS
RANK
DRSNS
TXMUTE
TELMUTE
IA-RESET
CUTI
HS
CI
CSWI
PESNS
FAX
FRSNS
ENGINE
ORGSNS
FC200
PSNS
VREFCONT
MDMRST
LEDON