Samsung ML 1710 Service Manual - Page 27

S U M M A RY OF PRO D U C T 4.3.1 ASIC (Jupiter IV) The Jupiter IV (16Bit RISC Processor), which is the executive controller to operate the printer function, is in use, and the each operation block is driven by system program of the flash memory. The whole system is controlled by driving operation block. •Main function block • Completely Integrated System for Embedded Applications, • 16 Bit Risc Architecture, Efficient and Powerful ARM7TDMI CPU • LSU Interface Module for Interfacing PVC or HPVC with LSU • 2 Channel General Purpose DMA Controller for High Speed I/O • Dual Memory Bus Architecture • Operating frequency : 80MHz • Operating power : 3.3V • Power on reset time : under 6.6ms 4.3.2 Flash Memory It stores the system program and downloads the system program through the PC interface. • Capacity : 0.5M Byte • Access Time : 70 nsec 4.3.3 SDRAM It is used as a swath buffer, system working memory area, etc. while printing. • Capacity : ML-1510 2 M byte ML-1710 8 M byte • Access Time : 60 nsec ML-1750 8 M byte 4.3.4 Sensor input circuit 1) Paper Empty Sensing The Paper empty sensor (Photo Interrupter) on the engine board informs the state of paper to CPU whether it is empty or not with operation of the actuator. When cassette is empty, it detects the fact by reading the D0 Bit of CPU, and then informs the fact by selecting the second LED(yellow) among the panel LEDs. 2) MP Sensing By operation of Actuator on the frame, the MP Sensor (Photo Interrupter) on the engine board informs the state of paper to CPU whether it is empty or not. It reads the D0 Bit of CPU for recognizing paper in MP, and paper is fed from MP if there is. Service Manual 4-10 Samsung Electronics