s3c4510b Samsung Semiconductor, Inc., s3c4510b Datasheet - Page 171

• Manufacturer Part Number: s3c4510b
• Description: 16/32-bit Risc Microcontroller
• Manufacturer: Samsung Semiconductor, Inc.

S3C4510B
The nEWAIT should be valid at the first SCLK falling edge after nOE active. In this case, tCOS and tCOH need
to have a minimum of one cycle, and by the setting of tCOS value slower device can be supported. Naimly,
nEWAIT valid time depends on tCOS value. Deassertion timing depends on the applied Ext. I/O devices.
When the nEWAIT de-assert, it must be synchronized with MCLKO rising edge.(Because we can not detect
SCLK falling edge.) If not, memory state machine can go into the wrong state.
Address
nEWAIT
MCLKO
SCLK
nECS
Data
nOE
tADDRd
tACS
Figure 4-13. External I/O Read Timing with nEWAIT
tNECS
tCOS
tWs
tNROE
tWh
Addr
tACC
tNROE
Data Read Point
tCOH
(tCOH = 1)
Data
tNECS
tACS = 1 (1 cycle)
tCOS = 1 (1 cycle)
tACC = 1 (2 cycles)
tCOH = 1 (1 cycle)
SYSTEM MANAGER
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