TC58256AFTI
Status Read
The device automatically implements the execution and verification of the Program and Erase operations. The
Status Read function is used to monitor the Ready/Busy status of the device, determine the result (pass/fail) of a
Program or Erase operation, and determine whether the device is in Protect mode. The device status is output
via the I/O port on the RE clock after a 70H command input. The resulting information is outlined in Table 5.
Table 5. Status output table
STATUS
I/O1
Pass/Fail
I/O2
Not Used
I/O3
Not Used
I/O4
Not Used
I/O5
Not Used
I/O6
Not Used
I/O7
Ready/Busy
I/O8
Write Protect
Pass: 0
0
0
0
0
0
Ready: 1
Protect: 0
OUTPUT
Fail: 1
The Pass/Fail status on I/O1 is only
valid when the device is in the Ready
state.
Busy: 0
Not Protected: 1
An application example with multiple devices is shown in Figure 6.
CE1
CE2
CE3
CLE
ALE
WE
RE
I/O1
~I/O8
RY/BY
Device
1
Device
2
Device
3
CEN
Device
N
CEN + 1
Device
N+1
RY/BY
Busy
CLE
ALE
WE
CE1
CEN
RE
I/O
70H
70H
Status on
Device 1
Status on
Device N
Figure 6. Status Read timing application example
System Design Note: If the RY/BY pin signals from multiple devices are wired together as shown in the
diagram, the Status Read function can be used to determine the status of each individual device.
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