Timing Diagrams (Continued)
ERASE CYCLE (ERASE)
tCS
CS
SK
DI
1 1 1 An An-1
A1 A0
tWP
Start Opcode
Address
Bit
Bits(2) High - Z Bits(8/9)
DO
Busy
93C66A (ORG=1; An=A7):
Address bits pattern -> A7-A6-A5-A4-A3-A2-A1-A0; User defined
Ready
93C66A (ORG=0; An=A8):
Address bits pattern -> A8-A7-A6-A5-A4-A3-A2-A1-A0; User defined
ERASE ALL CYCLE (ERAL)
tCS
CS
SK
DI
1 1 1 An An-1
A1 A0
tWP
Start Opcode
Address
Bit
Bits(2) High - Z Bits(8/9)
DO
Ready
Busy
93C66A (ORG=1; An=A7):
Address bits pattern -> 1-0-x-x-x-x-x-x; (x -> Don't Care, can be 0 or 1)
93C66A (ORG=0; An=A8):
Address bits pattern -> 1-0-x-x-x-x-x-x-x; (x -> Don't Care, can be 0 or 1)
CLEARING READY STATUS
CS
SK
DI
High - Z
DO
Busy
Ready
Start
Bit
High - Z
Note: This Start bit can also be part of a next instruction. Hence the cycle
can be continued(instead of getting terminated, as shown) as if a new
instruction is being issued.
NM93C66A Rev. E.1
10
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