Canon BJC 50 Service Manual - Page 94

Part 4: Technical Reference BJC-50 The HEAT ENABLE signals control the ejection of small and large ink droplets as follows: For each color, (Y, M and C), HENB B and A signals drive the front and back nozzle heaters respectively. For black, HENB C and D signals drive the front and back nozzle heaters respectively. The HEAT ENABLE signal consists of the pre-pulse and the main pulse that optimize ink ejection by constantly monitoring the head rank, the printer inner temperature and head temperature. The ink is ejected by varying the HEAT ENABLE pulse width. 164µs (6.43kHz) 164µs (6.43kHz*) 92µs (7.82kHz) HQ 720dpi/smoothing HS HLATCH HDATA HCLOCK Odd ENB Even ENB B ENB 0 B ENB 1 B ENB 2 H ENB A, B, C, D 1(0) 0(1) 1(0) 0 1 2 3 4 128 or 136 Data transmission to shift resistor 0(1) 1(0) 0(1) Head Drive in HQ Mode (Divided into 16) 1(0) 0(1) 1 Block Odd ENB Even ENB B ENB 0 B ENB 1 B ENB 2 H ENB A, B, C, D 1(0) 0(1) 1(0) 0(1) 0(1) 1(0) 0(1) 1(0) 0(1) 0(1) 1(0) 1(0) Head Drive in HS Mode (Divided into 8) Pre-Pulse Variable Pulse Width 1(0) 0(1) Main Pulse 1 Block Odd ENB Even ENB B ENB 0 B ENB 1 B ENB 2 H ENB A, D H ENB B, C Head Drive in 720dpi (Divided into 8) Large and small dot printing 1 Block When using a black BJ cartridge, HENEB A and D are drive signals. When using the color BJ cartridge, HENEB A and B drive yellow, magenta and cyan, and HENEB C and D drive black. Figure 4-4 Print Signals 4-6