Panasonic KX-FP342BX, Service Manual

Page: 124 / 217

NO. SIGNAL I/O POWER SUPPLIED
VOLTAGE
DESCRIPTION
123 RM3/IOP O 3.3V RX MOTOR /B PHASE
124 RXE/IOP O 3.3V RX MOTOR ENABLE SIGNAL
125 TMO O 3.3V TX MOTOR A PHASE
126 VDD (2.5V) 3.3V POWER SOURCE (+2.5V)
127 VSS GND POWER SOURCE (GND)
128 TM1/IOP O 3.3V TX MOTOR B PHASE
129 TM2/IOP O 3.3V TX MOTOR /A PHASE
130 TM3/IOP O 3.3V TX MOTOR /B PHASE
131 TXE/IOP O 3.3V TX MOTOR ENABLE SIGNAL
132 KSTART O 3.3V OPERATION PANEL CONTROL
133 KLATCH O 3.3V OPERATION PANEL CONTROL
134 KSCLK O 3.3V OPERATION PANEL CONTROL
135 KTXD O 3.3V OPERATION PANEL CONTROL
136 KRXD I 3.3V OPERATION PANEL CONTROL
137 FMEMCLK/IOP O 3.3V OUTPUT PORT (THON)
138 FMEMDI/IOP O 3.3V OUTPUT PORT (LINERLY)
139 ADSEL1 O 3.3V CHANNEL SELECT SIGNAL FOR AIN2
140 VDDA (2.5V) 3.3V POWER SOURCE (2.5V)
141 VREFB A 2.5V A/D CONVERTER´S ZERO STANDARD VOLTAGE
OUTPUT
142 VCL A 3.3V ANALOG PART STANDARD VOLTAGE SIGNAL
143 VREFT A 3.3V A/D CONVERTER´S FULL SCALE VOLTAGE
OUTPUT
144 VSSA GND POWER SOURCE (ANALOG GND)
7.3.6. RESET CIRCUIT (WATCH DOG TIMER)
The output signal (reset) from pin 4 of the voltage detect IC (IC507) is input to the ASIC (IC501) 114 and 106 pins.
1. During a momentary power interruption, a positive reset pulse of 50~70 msec is generated and the system is reset completely.
2. The watch dog timer, built-in the ASIC (IC501), is initialized by the CPU about every 1.5 ms.
When a watch dog error occurs, pin 115 of the ASIC (IC501) becomes low level.
The terminal of the ´WDERR´ signal is connected to the reset line, so the ´WDERR´ signal works as the reset signal.
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KX-FP342BX