Preliminary W928C73
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Read mode
This mode will read out the data from the flash ROM. The first 24 bits of DATA are the starting frame
address of reading-out. If DATA is low for these 24 bits, then the output data will start from address
"0". The stored data will shift out bit by bit with each clock in. The LSB of data is shifted out first.
Program mode
This mode will write data into the flash ROM. This flash ROM is programmed on a frame basis. Each
frame contains 32 bits of data. The LSB of data is shift in first. The programming time (Tpr) must be
more than 400
µ
S. Each programming pulse will increase the frame address by 1.
Erase Mode
This mode will erase all the data in the flash ROM. The typical whole-chip-erase time should be larger
than 50 mS (Twe).
TIMING WAVEFORMS
Flash ROM Programming
T
T
1/F
CLK
DATA
Write Cycle
T
T
1/F
CLK
DATA
Read Cycle
CLK
RH
RA
WH
WS
CLK
T
T
1/F
ADDR
DATA
Address Shift-in Cycle
T
T
MODE
CTRL
Mode Select Duration
1/F
ME
CTRL
MB
ADDR
AS
AH