Epson DFX-9000 Service Manual page 88

Epson DFX-9000
Memory circuit control
As shown in the figure below, the memory circuit consists of three
memory devices: Flash memory, D-RAM, and F-RAM. Brief
descriptions for each memory device are given below.
Flash memory
16 Mbit of Flash memory are used to store the control program
(firmware) and character generator data.
D-RAM
16 Mbit of DRAM are used as the work area for data processing and
print image data generation.
F-RAM
4 Kbit of F-RAM are used to store mechanical adjustment parameters
and operational history information (error log, print operation log, etc.)
The CPU communicates with this chip through a two-line serial
interface (Data signal, Clock signal).
Operating Principles
SoC ASIC
(LSI1)
XCE8(XRAS1)
XCE7
Figure 2-24. Memory control circuit block diagram
Circuit operation
Flash Memory
(IC1)
XCE10EX
D-RAM
(IC3)
ASIC
(LSI2)
FRAMDO/FRAMCLK
FRAM
Revision B
XWRL
XRD
XUCAS,XLCAS
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