Super Star 4900B, Service Manual

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Main PCB
IC-7
TMP87CM21DF
CPU Pin Assignment
NO. PIN NAME REMARK DESCRIPTION ACTIVE
1 VSS GROUND
2
XOUT 4.0MHz HIGH FREQUENCY CLOCK OUT
3
XIN 4.0MHz HIGH FREQUENCY CLOCK IN
4
RESET RESET INPUT HIGH
5 P22 (XOUT) OPEN DRAIN DIMMER OUT1
6 P21 (XTIN) OPEN DRAIN DIMMER OUT2
7
TEST FOXED TO LOW (GROUND)
8
P20 (INT5/STOP) OPEN DRAIN MODE IN (IN)
9 P40 (INT3/TC3) TRI STATE N.C
10
P41 (PWM/PDO) TRI STATE BEEP TONE OUT FOR
1750HZ(OUT)
11
P42 (SCK1) TRI STATE SQ OUT (OUT) HIGH: SQ ON
12
P43 (S11) TRI STATE ASC CONTROL (OUT) HIGH: ASC ON
13
P44 (S01) TRI STATE ANL CONTROL (OUT) ACTIVE “H”
14 P45 (SCK2) TRI STATE NB CONTROL (OUT) ACTIVE “H”
15 P46 (S12) TRI STATE MODE IN (IN)
16
P47 (S02) TRI STATE DTMF ENCODER ENABLE (OUT)
17 P10 (INT0) TRI STATE ROTARY CHANNEL UP (IN) ACTIVE “L”
18 P11 (INT1) TRI STATE ROTARY CHANNEL DN (IN) ACTIVE “L”
19
P12 (INT2/TC1) TRI STATE DTMF ENCODER ENABLE (OUT)