Epson SEIJ98006 manual EEPROM Control Driver Circuit, 22. EEPROM Control Circuit Block Diagram

EPSON Stylus Color 900 Revision C

2.3.9 EEPROM Control Driver Circuit

Data for various factory-adjustment items is stored in the EEPROM (IC7) on the C265 main board. The size of the EEPROM is 2 K bit since various types of dots are available with this printer and memory allocated for the ink consumption counter is accordingly large.

When the printer is turned on, data stored in the EEPROM is transferred to the D-RAM by the ASIC (IC3). In the D-RAM, the ASIC controls various adjustment values, total ink consumption, and current ink usage condition for each color, and the printer prints depending on these values. When the printer is turned off, the data and adjustment values accumulated and controlled in the D-RAM are written back into the specific addresses in the EEPROM under the ASIC’s control. Information is transmitted between the ASIC (IC3) and the EEPROM in the serial data format.

+ 5	E 0 5 A 6 0 ( I C 3 ) D R A M ( I C 5 )
A T 9 3 C 5 6 ( I C 7 )

				C
8			V c c
		6		S
			O R G
	5			D
			G N D
				D

1	2	9
S		E C S
2	3	0
K		E S K	A d d	s
3	3	1
			D a t
I		E D I
4	3	2
O		E D O

Figure 2-22. EEPROM Control Circuit Block Diagram

Operating Principles Electrical Circuit Operation Principles 77