Epson L-1000 Technical Manual page 61

REV.-A
PRINCIPLES OF OPERATION
Module Installation or Removal
Figure 2-28 shows the RESET pulse generation process that occurs when a ROM cartridge is mounted. Numbers
in parentheses below correspond to circled numbers in the figure. After the ROM cartridge is mounted, the
LOW signal flows into the CAR terminal of the gate array (6C), and a LOW signal is correspondingly output
from the DISC terminal and RESET is output from the ROUT terminal.
As the DISC terminal goes LOW, capacitor C26 is discharged with a time constant = R70 x C26. When
the discharge of C26 reduces the potential at the THLD terminal to threshold voltage Vth, the RESET signal
is canceled, and the DISC terminal goes HIGH. After the DISC terminal goes HIGH, Vx voltage
discharges C31 at time constant = R69 x C26 again.
Figure 2-28. RESET Pulse Oscillation Process (Module Mounted)
2-24
LQ-500/L-1000