© 2005 Microchip Technology Inc.
93AA86A/B/C, 93LC86A/B/C, 93C86A/B/C
Write All (WRAL)
The Write All (WRAL) instruction will write the entire
memory array with the data specified in the command.
The self-timed auto-erase and programming cycle is
initiated by the rising edge of CLK on the last data bit.
Clocking of the CLK pin is not necessary after the
device has entered the WRAL cycle. The WRAL
command does include an automatic ERAL cycle for
the device. Therefore, the WRAL instruction does not
require an ERAL instruction, but the chip must be in the
The DO pin indicates the Ready/Busy status of the
device if CS is brought high after a minimum of 250 ns
VCC must be
≥ 4.5V for proper operation of WRAL.
The write sequence requires a logic high
signal on the PE pin prior to the rising
edge of the last data bit.
After the Write All cycle is complete,
issuing a Start bit and then taking CS low
will clear the Ready/Busy status from DO.