42114101 Rev.1
12 /
(3)
RAM
The RAM is CMOS dynamic RAM with 256K
×
16-bit (4M bit), and used as buffers (such
as receiving buffer, printing buffer, DLL buffer and working buffer).
The following shows the examples of the memory access operation.
* Clockout is provided when the original excitation is selected.
A0~A8
CAS-N
RAS-N
UCAS-N
LCAS-N
WR-N
RD-N
WRH-N
WRL-N
RAM
MPU
P03
CS1
WRL
P11
RD
OE
D0~D15
RAS
UCAS
LCAS
WE
T1
T2
T3
Clockout*
A0~A8
RAS-N
VCAS-N
LCAS-N
RD-N
D0~D15
(Read)
WR-N
D0~D15
(Write)
16-bit bus, Word instruction
ALS139
ALS11
T4
Summary of Contents for ML490 Series
Page 1: ...42114101 Rev 1 1 135 ML490 491 PRINTER Maintenance Manual ODA...
Page 2: ...42114101 Rev 1 2...
Page 38: ...42114101 Rev 1 38 Drive gear Ink tank Ribbon cartridge Figure 2 6...
Page 48: ...42114101 Rev 1 48 Change arm Change lever Platen Release cam Figure 2 13 REAR TOP BOTTOM...
Page 96: ...42114101 Rev 1 96 9 Carriage Assy NK2 10 SUS Bearing portion of guide roller EM 30L B...
Page 119: ...42114101 Rev 1 119 6 8 9 7 1 2 3 11 10 4 5 Figure B 2 Printer General Assy...
Page 124: ...42114101 Rev 1 124 9 12 11 1 13 3 7 1 14 5 6 7 2 10 8 Figure B 4 Carriage Assy...