Epson Photo750 manual 2 C259 Main Control Circuit, Major Elements, Location Function

EPSON Stylus Photo 750 Revision A

2.2.2 C259 Main Control Circuit

Printer mechanism is controlled by C259 main board. The figure below shows the block diagram of C259 main control circuit.

	CN3 USB
P-ROM	Cartridge Sensor
(IC3)	Head			CN9 HD FFC			CR Motor
D-RAM		Batt1	CR1
						Q2&Q3
(IC4)
							PF Motor
	CN1 Parallel		Timer		Common
			Counter		Driver
	Buffer		(IC8)		(IC14)		CN7
	(IC9)						CN8
			EEPROM
M-ROM				Reset IC		Motor
			(IC7)		(IC9)	Driver	Motor
(IC6)
						(IC11)	Driver
							(IC12)
	E05B588						Motor
	(IC2)
C90A05							Driver
(IC1)							(IC13)
	Address			CN11
	Data
							C209 PNL
				CN6
			CN4
	Transceiver		CN5				ASF Sensor
	(IC9)
CN2 Mac. Serial		PE Sensor			HP Sensor
							op04

Figure 2-4. Control Circuit Block Diagram

2.2.2.1 Major Elements

Major elements used in C259 main control circuit board are below.

Table 2-2. Major Elements

IC	Location		Function
CPU		16bit CPU mounted on the control circuit board
	IC1	is driven by 24MHz clock frequency, and
C90A05CA
		controls the whole printer.
		•	Motor control
		•	Head voltage control
Gate Array		•	EEPROM control
	IC2	•	Monitoring the sensor
E05B58**
		•	Monitoring Timer IC
		•	Mac,Serial I/F, running direction parallel I/F,
			USB I/F control
		Volume 4/8/16MB, Bus width 16 bit EEPROM
PROM	IC3	• Program or program +CG(k character
			generator)
RAM	IC4	Bus width 16 bit, 4Mbit DRAM
Mask ROM	IC6	64Mbit Mask ROM
		•	CG
		1kBit EEPROM
AT93C46	IC7	•	Default Setting Value
		• Back-up of various parameter
RTC-9810SA	IC8	Reset/Timer IC
74VHC161284	IC9	Transceiver IC
MEA
SN75LBC777	IC10	RS-422/423 Transceiver
LB1847	IC11	CR motor drive iC
A3956ALB	IC12,13	PF/PUMP Motor drive IC
CXA2099S	IC14	Head drive control HIC
		• Generating head common voltage

Operating Principles Operating Principles of Electric Circuit 32