Xerox WorkCentre Pro 412, Service Manual

Page: 40 / 192

Circuit Description
WorkCentre Pro 412
Launch Issue
5-14
August 2001
5-2-5-2 FPM DRAM Write Timing
5Mhz
MCLK
DRAMD
nWE
nOE
DRAMA
nCAS
nRAS
Trp Trc Tcas Tcas
dat a 1
dat a 0
r ow address
column address
column address
addr
wait wait dat a
dat a
clock type
Trp Trc Tcas
cycle # register cycle # register cycle # register
58Mhz
40 ns FPM 2 0x1 2 0x1 1 0x0
50 ns FPM 2 0x1 2 0x1 1 0x0
60 ns FPM 3 0x2 2 0x1 2 0x1
70 ns FPM 3 0x2 2 0x1 2 0x1
FPM Write Timing Diagram
SFR Values Example for FPM