11AA02UID
TABLE 4-2:
INTERNAL ADDRESS
COUNTER
4.2
Current Address Read (CRRD)
Instruction
Command
Event
Action
The internal address counter featured on the
11AA02UID maintains the address of the last memory
array location accessed. The CRRDinstruction allows
the master to read data back beginning from this
current location. Consequently, no word address is
provided upon issuing this command.
—
Power-on Reset Counter is undefined
Read or
Write
MAK edge
following each
Address byte
Counter is updated
with newly received
value
Read,
Write, or
CRRD
MAK/NoMAK
edge following
each data byte
Counter is incre-
mented by 1
Note that, except for the initial word address, the
READ and CRRD instructions are identical, including
the ability to continue requesting data through the use
of MAKs in order to sequentially read from the array.
Note:
If, following each data byte in a READ,
WRITE, or CRRD instruction, neither a
MAK nor a NoMAK edge is received (i.e.,
if a standby pulse occurs instead), the
internal address counter will not be incre-
mented.
As with the READinstruction, the CRRDinstruction is
terminated by transmitting a NoMAK.
Table 4-2 lists the events upon which the internal
address counter is modified.
Note:
During a Write command, once the last
data byte for a page has been loaded, the
internal Address Pointer will rollover to the
beginning of the selected page.
FIGURE 4-2:
CRRD COMMAND SEQUENCE
Device Address
Standby Pulse
Start Header
SCIO
0 1 0 1 0 1 0 1
1 0 1 0 0 0 0 0
Command
Data Byte 1
Data Byte 2
7 6 5 4 3 2 1 0
7 6 5 4 3 2 1 0
SCIO
SCIO
0 0 0 0 0 1 1 0
Data Byte n
7 6 5 4 3 2 1 0
DS20005206A-page 10
2013 Microchip Technology Inc.
MICROCHIP [ MICROCHIP ]
