93AA66A/B/C, 93LC66A/B/C, 93C66A/B/C
DS21795B-page 6 2003 Microchip Technology Inc.
2.4 ERASE
The ERASE instruction forces all data bits of the speci-
fied address to the logical ‘1’ state. CS is brought low
follow ing the l oading o f the las t address b it. This f alling
edge of the CS pin initiates the self-timed program-
ming cycle, except on ‘93C’ devices where the rising
edge of CLK before the last address bit initiates the
write cycle.
The DO pin indicates the READY/BUSY
status of the
device if CS is brought high after a minimum of 250 ns
low (TCSL). DO at logical ‘0’ indicates that programming
is still in progress. DO at logical ‘1’ indicates that the
register at the specified address has been erased and
the device is ready for another instruction.
Note: Issuing a Start bit and then taking CS low
will clear the READY/BUSY
status from
DO.
FIGU RE 2-1 : ERASE T I MI NG FO R 9 3A A AN D 93L C DE VIC E S
FIGURE 2-2: ERASE TIMING FOR 93C DEVICES
CS
CLK
DI
DO
T
CSL
CHECK STATUS
1
1
1A
N
AN-1 AN-2
•••
A0
T
SV TCZ
BUSY READY
HIGH-Z
T
WC
HIGH-Z
CS
CLK
DI
DO
T
CSL
CHECK STATUS
1
1
1A
N
AN-1 AN-2
•••
A0
T
SV TCZ
BUSY READY
HIGH-Z
T
WC
HIGH-Z
