HD61202U Datasheet, PDF (10/33 Pages) Hitachi Semiconductor – Dot Matrix Liquid Crystal GraphicDisplay Column Driver

HD61202U
Busy Flag
Busy flag = 1 indicates that HD61202U is operating and no instructions except status read instruction can
be accepted. The value of the busy flag is read out on DB7 by the status read instruction. Make sure that
the busy flag is reset (0) before issuing instructions.
D/I
R/W
E
Address
Output
register
DB0–DB7
N
N+1
N+2
Busy
check
Write
address N
Busy
check
Read data
(dummy)
Data at address N Data at address N + 1
Busy
check
Read
data at
address N
Busy
check
Data read
address
N+1
Figure 1 MPU Read Timing
E
Busy
flag
T Busy
1/f_CLK ≤ T Busy ≤ 3/f_CLK
f_CLK is ø1, ø2 frequency
Figure 2 Busy Flag
825