93AA46AE48
DS20005229C-page 8 2013-2016 Microchip Technology Inc.
2.6 Erase/Write Disable and Enable
(EWDS/EWEN)
The 93AA46AE48 powers up in the Erase/Write
Disable (EWDS) state. All programming modes must
be preceded by an Erase/Write Enable (EWEN)
instruction. Once the EWEN instruction is executed,
programming remains enabled until an EWDS
instruction is executed or Vcc is removed from the
device.
To protect against accidental data disturbance, the
EWDS instruction can be used to disable all erase/write
functions and should follow all programming
operations. Execution of a READ instruction is
independent of both the EWEN and EWDS instructions.
FIGURE 2-3: EWDS TIMING
FIGURE 2-4: EWEN TIMING
2.7 Read
The READ instruction outputs the serial data of the
addressed memory location on the DO pin. A dummy
zero bit precedes the 8-bit output string.
The output data bits will toggle on the rising edge of the
CLK and are stable after the specified time delay (T
PD).
Sequential read is possible when CS is held high. The
memory data will automatically cycle to the next register
and output sequentially.
CS
CLK
DI
10
000x
•••
x
TCSL
1x
CS
CLK
DI
00 1 1x
TCSL
•••
