AM29F100 AMD [Advanced Micro Devices], AM29F100 Datasheet - Page 18

• Manufacturer Part Number: AM29F100
• Description: 1 Megabit (128 K x 8-bit/64 K x 16-bit) CMOS 5.0 Volt-only, Boot Sector Flash Memory
• Manufacturer: AMD [Advanced Micro Devices]

than 50 s. See also the “Sector Erase Command Se-
quence” section.
After the sector erase command sequence is written,
the system should read the status on DQ7 (Data# Poll-
ing) or DQ6 (Toggle Bit I) to ensure the device has ac-
cepted the command sequence, and then read DQ3. If
DQ3 is “1”, the internally controlled erase cycle has be-
gun; all further commands (other than Erase Suspend)
are ignored until the erase operation is complete. If
DQ3 is “0”, the device will accept additional sector
erase commands. To ensure the command has been
accepted, the system software should check the status
of DQ3 prior to and following each subsequent sector
erase command. If DQ3 is high on the second status
check, the last command might not have been ac-
cepted. Table 6 shows the outputs for DQ3.
18
Am29F100
Notes:
1. Read toggle bit twice to determine whether or not it is
2. Recheck toggle bit because it may stop toggling as DQ5
toggling. See text.
changes to “1”. See text.
No
Figure 5. Toggle Bit Algorithm
Complete, Write
Reset Command
Read DQ7–DQ0
Read DQ7–DQ0
Read DQ7–DQ0
Program/Erase
Operation Not
Toggle Bit
Toggle Bit
DQ5 = 1?
= Toggle?
= Toggle?
START
Twice
Yes
Yes
Yes
(Notes
1, 2)
1
Operation Complete
No
No
Program/Erase
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