20.11.4 Auto-Program Mode - Hitachi H8S/2646 Hardware Manual

Hitachi 16-bit single-chip microcomputer h8s/2646 series
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A18–A0
CE
OE
WE
V
IH
I/O7–I/O0
Figure 20-21 CE and OE Clock System Read Timing Waveforms

20.11.4 Auto-Program Mode

1. In auto-program mode, 128 bytes are programmed simultaneously. This should be carried out
by executing 128 consecutive byte transfers.
2. A 128-byte data transfer is necessary even when programming fewer than 128 bytes. In this
case, H'FF data must be written to the extra addresses.
3. The lower 7 bits of the transfer address must be low. If a value other than an effective address
is input, processing will switch to a memory write operation but a write error will be flagged.
4. Memory address transfer is performed in the second cycle (figure 20-22). Do not perform
transfer after the third cycle.
5. Do not perform a command write during a programming operation.
6. Perform one auto-program operation for a 128-byte block for each address. Two or more
additional programming operations cannot be performed on a previously programmed address
block.
7. Confirm normal end of auto-programming by checking I/O6. Alternatively, status read mode
can also be used for this purpose (I/O7 status polling uses the auto-program operation end
decision pin).
8. Status polling I/O6 and I/O7 pin information is retained until the next command write. As long
as the next command write has not been performed, reading is possible by enabling CE and
OE.
702
Address stable
t
ce
t
oe
t
acc
t
oh
Address stable
t
ce
t
oe
t
acc
t
df
t
df
t
oh

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