EPSON Stylus COLOR 3000

2.3.2.1 Reset Circuits

The ￿￿￿￿ MAIN board contains two reset circuits: for logic line (+5 ￿) and power line (+42 ￿). Reset IC M51955BFP (IC3) monitors the +42 ￿ line. It outputs /NMI signal to the ￿￿ and the gate array to cut off the power line for the motors when the voltage level drops below 33.2 ￿. Reset IC RST592D (IC9) monitors the +5 V line and sends low pulse when the voltage level drops below 4,2 ￿. While the printer power is on, it outputs ￿￿￿ until stabilized +5 ￿ is produced to ensure the ￿￿ ’s proper operation.

+5V

RST592D

(IC9)

GA

+42VVOUT RESET E05B45 (IC16)

M51955BFP

(IC3)

 

NC5

 

 

 

RES

RESET

GA

 

 

 

CPU

 

 

 

 

 

 

 

 

 

 

 

 

E05B33

 

 

 

NMI

H8S/2655

 

 

 

OUT

 

 

 

(IC6)

 

 

 

(IC5)

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Figure 2-16. Reset Circuit Block Diagram2.3.2.2 Sensor Circuits

￿￿and the gate array E05B45 (IC 16) monitor printer condition referring to the signals from 13 sensors described below

￿HP : Output from the HP(Home Position) sensor.

The ￿￿ sensor for this printer uses the reliable photo interrupter system. the signal ￿￿ is ￿￿￿ when the ￿￿ unit is at the home position, and is ￿"￿￿ when it is not at the home position.

￿PE_R : Output from the rear PE (Paper End) sensor.

The rear ￿￿ sensor, attached to the rear part of the paper path, detects paper presence condition for continuous paper or cut sheet set in the rear paper slot. A mechanical switch is used for this sensor and the signal ￿￿&￿ is ￿"￿￿ with paper detected and ￿￿￿ without any paper detected.

￿PE_F : Output from the front PE (Paper End) sensor.

The front ￿￿ sensor, located in the paper guide unit, detects paper presence condition for ￿￿￿. This sensor uses a mechanical switch and the signal ￿￿&￿ is ￿"￿￿ with paper detected and is ￿￿￿ without any paper detected.

￿REL : Output from the release sensor.

Release sensor is built into the rear part of the left frame in the printer mechanism. It determines whether the release lever is set to the cut sheet side (friction mode) or to the continuous paper side (tractor mode). The signal REL is ￿￿￿ when the lever is set to the friction mode and is ￿"￿￿ when the lever is set to the tractor mode.

￿CO_B/C/M/Y :Output from each ink cartridge sensor.

The ink cartridge sensor for each color is individually attached to the ink cartridge holder in the printer mechanism. It determines whether the corresponding ink cartridges is installed or not. A mechanical switch is used for this sensor and the signals ￿￿&$￿￿￿!￿' is ￿￿￿ when the cartridge is installed and is

￿￿￿ when the cartridge is not installed. When the sensor detects no cartridge condition, the ink consumption counter is reset.

￿IE_B/C/M/Y : Output from each ink end sensor.

The ink end sensor for each color, individually attached to the ink cartridge holder in the printer mechanism, detects ink end condition*. It uses the mechanical switch system and the signal IE_B/C/M/Y is ￿￿￿ or ￿"￿￿ on the ink left or end condition, respectively. If the ink end condition is detected while the ink cartridge is detected by the ink cartridge sensor, the ink consumption counter is

reset.

Note) The ink end sensor detects an ink end condition when the remainder of the ink drops to 5 % of the capacity.

Rev. A

2-17