Sharp FO-3150, Руководство по обслуживанию

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FO-3150U/C
5 – 10
(6) IC8 (
µ
PD65944) Hardware description
1) ASIC Functional Description
• Serial data reception from FaxEngine
• FaxEngine external bus connection
• Print data smoothing
• Resolution change and image scaling (50% to 200%)
Horizontal scanning 203.2dpi -> 406.4dpi
Vertical scanning 97.79dpi (Standard)/195.58dpi (Fine)/391.16dpi (SuperFine) -> 391.16dpi
• Centering in horizontal scanning direction
• Buffer memory, page buffer control (SDRAM) and memory access control
• Compatible with multiple copying (repeat printing)
• Laser control, video signal output control
• Polygon motor/main charge drive waveform generation
• Pickup solenoid and heater lamp driven hardware protection
• Serial interface between microcomputer for engine control and
µ
PD780032A (PrinterEngine)
2) Print Data Conversion Process
Fig. 6 Print Data Conversion Process
Serial data
Standard
Input resolution
Serial input
buffer
203.2 x 97.79 dpi
Fine 203.2 x 195.58 dpi
Super Fine 203.2 x 391.16 dpi
406.4 x 391.16 dpi
1728 dot/line 3456 dot/line 3456 dot/line
Smoothing
Vertical scan
resolution change
Intermediate
buffer
Enlarge/reduce
Centering in horizontal
scan direction
Page buffer Video data
Print resolution
406.4 x 391.16 dpi
406.4 x 391.16 dpi
406.4 x 391.16 dpi
406.4 x 391.16 dpi
406.4 x 391.16 dpi
3) ASIC Constitution
Fig. 7 ASIC Constitution
Serial data
reception
circuit
Interrupt
Controller
Fax Engine
Bus Interface
Memory
Arbitrator
All data
conversion
controller
(page control)
SDRAM
Controller
Memory
Bus
x16 SDRAM
64Mbit
Local Bus-A
ASIC
Serial input
buffer
1.5 MB
Smoothing
process
circuit
Intermediate
buffer
512 KB
Scale
conversion
circuit
Page
buffer
6 MB
Video
output
Interface
Laser Printer Unit
Printer Engine
Bus Interface
Microcomputer
for engine control
(PrinterEngine)
Hardware
protection
timer
Interrupt
Controller
Local Bus-B
Printer Engine
Bus I/F
Polygon
main charger
control
Fax Engine
Serial Data I/F FAX Engine Bus I/F
CLK
32.256MHz
32.256
MHz
System Clock
20.95261MHz
Output control
for page conversion
completion signal