THEORY
Electrical
SERVICE MANUAL
2-18
8.3.
Keyboard Control Circuit
The keyboard control circuit is shown in Fig. 2.18.
The matrix pattern on the keyboard FPC controls port 7 (0:7) of CBIC (#8) according to
data signals KO0 through KO8. The LOW level signals are output to output lines KO0
through KO8. The electrode wiring is scanned line by line. The result of scanning is
input to P70 through P77 of CBIC (#8). CBIC (#8) detects which key has been pressed.
The key matrix given in Fig. 2.19 corresponds to the key arrangement shown in Fig.
2.20.
Fig. 2.18 Keyboard Control Circuit
Summary of Contents for DP-550CJ
Page 15: ...THEORY SERVICE MANUAL Mechanical 1 3 Fig 1 2 General View of Printing Mechanism ...
Page 20: ...THEORY Mechanical SERVICE MANUAL 1 8 Fig 1 7 Printer Flat Cable to Cartridge Alignment ...
Page 21: ...THEORY SERVICE MANUAL Mechanical 1 9 Fig 1 8 Ink Jet Cartridge to Flat Cable Alignment ...
Page 33: ...THEORY SERVICE MANUAL Mechanical 1 21 Fig 1 17 LCD Unit Installation in the Upper Cover ...
Page 34: ...THEORY Mechanical SERVICE MANUAL 1 22 DP 525CJ LW 800ic Fig 1 18 LCD of DP 525CJ LW 800ic ...
Page 38: ...THEORY Electrical SERVICE MANUAL 2 2 Fig 2 1 Major Electronic Component Parts ...
Page 80: ...REPAIR SERVICE MANUAL Troubleshooting 3 17 Fig 3 5 Results of Self Print Test ...
Page 118: ...REPAIR SERVICE MANUAL Mechanical 4 3 Fig 4 2 Removing the Sub Paper Support and Paper Support ...
Page 124: ...REPAIR SERVICE MANUAL Mechanical 4 9 Fig 4 6 Removing the LCD Unit ...
Page 127: ...REPAIR Mechanical SERVICE MANUAL 4 12 DP 525CJ LW 800ic Fig 4 8 Removing the LCD PCB 1 ...
Page 128: ...REPAIR SERVICE MANUAL Mechanical 4 13 DP 530CJ LW 810ic Fig 4 9 Removing the LCD PCB 2 ...
Page 129: ...REPAIR Mechanical SERVICE MANUAL 4 14 LW 810icBL Fig 4 10 Removing the LCD PCB 3 ...
Page 130: ...REPAIR SERVICE MANUAL Mechanical 4 15 DP 540CJ Fig 4 11 Removing the LCD PCB 4 ...
Page 131: ...REPAIR Mechanical SERVICE MANUAL 4 16 DP 550CJ LW 840ic Fig 4 12 Removing the LCD PCB 5 ...
Page 134: ...REPAIR SERVICE MANUAL Mechanical 4 19 Fig 4 14 Installing LCD Latch ...
Page 139: ...REPAIR Mechanical SERVICE MANUAL 4 24 Fig 4 18 Installing the Hinge Assy ...
Page 154: ...REPAIR SERVICE MANUAL Mechanical 4 39 Fig 4 30 Removing the Hopper Assembly ...
Page 162: ...REPAIR SERVICE MANUAL Mechanical 4 47 Fig 4 38 Removing the Carriage ...
Page 171: ...REPAIR Mechanical SERVICE MANUAL 4 56 Fig 4 45 Measuring Friction during Carriage Movement ...
Page 178: ...REPAIR Mechanical SERVICE MANUAL 5 2 Fig 5 1 Carriage Assembly Lubrication Points ...
Page 179: ...REPAIR SERVICE MANUAL Mechanical 5 3 Fig 5 2 Paper Feed Assembly Lubrication Points ...
Page 194: ...Feb 98 53T010BE1 R ...