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CHAPTER 3 THEORY OF OPERATION
3-5
1.3
Main PCB
1.3.1
ASIC
A Fujitsu 32bit RISC CPU, MB86833 (SPARC lite) is built in the ASIC. While the CPU is driven
with a clock frequency of 33 MHz in the user logic block, it itself runs at 66 MHz, which is
generated by multiplying the source clock by two.
The functions of the interface block communication with external devices are described below;
(1) IEEE1284
Stores the data received from the PC into DRAM as controlled by the DMA controller. It is
applicable to both normal receiving and bi-directional communication (nibble mode, byte
mode, ECP mode).
(2) USB interface
Stores the data received from the PC into DRAM as controlled by the DMA controller. The
transmission speed is 12Mbps.
(3) Engine GA transfer circuit
Communicates with the engine GA by a full-duplex synchronous serial method. The
communication speed is 2Mbps.
Fig. 3-5
HL-1240
Summary of Contents for HL-1240
Page 1: ......
Page 45: ...CHAPTER 3 THEORY OF OPERATION 3 7 Fig 3 6 ...
Page 102: ...CHAPTER 4 DISASSEMBLY AND RE ASSEMBLY 4 38 ...
Page 110: ...CHAPTER 5 PERIODIC MAINTENANCE 5 8 ...
Page 176: ...CODE UK4352000 B512040CIR 1 2 A 18 NAME Appendix 10 Main PCB Circuit Diagram HL 1240 1 2 ...
Page 177: ...Appendix 11 Main PCB Circuit Diagram HL 1240 2 2 CODE UK4352000 B512040CIR 2 2 A 19 NAME ...
Page 178: ...Appendix 12 Main PCB Circuit Diagram HL 1250 1 5 CODE UK4361000 B512049CIR 1 5 A 20 NAME ...
Page 179: ...Appendix 13 Main PCB Circuit Diagram HL 1250 2 5 CODE UK4361000 B512049CIR 2 5 A 21 NAME ...
Page 180: ...CODE UK4361000 B512049CIR A 22 NAME Appendix 14 Main PCB Circuit Diagram HL 1250 3 5 ...
Page 181: ...CODE UK4361000 B512049CIR 4 5 A 23 NAME Appendix 15 Main PCB Circuit Diagram HL 1250 4 5 ...
Page 182: ...CODE UK4361000 B512049CIR 5 5 A 24 NAME Appendix 16 Main PCB Circuit Diagram HL 1250 5 5 ...
Page 183: ...Appendix 17 Engine PCB Circuit Diagram CODE UK4444000 B512059CIR A 25 NAME ...
Page 192: ...INDEX vi ...
Page 321: ...A 12 HP LaserJet IIP HP LaserJet 6P HL 1250 only ...
Page 323: ...A 14 HP LaserJet IIP 6P EPSON FX 850 IBM Proprinter XL EPSON FX 850 ...