Datasheet

AT30TSE752A/754A/758A [DATASHEET]
Atmel-8854G-DTS-AT30TSE752A-754A-758A-Datasheet_102014
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9. Other Commands
The AT30TSE752A/754A/758A incorporates additional commands for other device functions. The command opcode
consists of a single byte of data that is sent from the Master to the AT30TSE752A/754A/758A in place of the Pointer
Register byte; therefore, the device must first be addressed by the Master and then given the subsequent command
opcode. Sending any of the command opcodes to the AT30TSE752A/754A/758A will not change the contents of the
Pointer Register byte.
Table 9-1. Command Listing
Figure 9-1. Command Loading
9.1 Copy Nonvolatile Registers to Volatile Registers
The Copy Nonvolatile Registers to Volatile Registers command allows the contents of the Nonvolatile Configuration
Register, Nonvolatile T
LOW
Limit Register, and Nonvolatile T
HIGH
Limit Register to be copied into the Configuration
Register, T
LOW
Limit Register, and T
HIGH
Limit Register. The copy process is automatically performed upon power-up or
reset, but the Copy Nonvolatile Registers to Volatile Registers command provides the ability to re-copy the data registers
if needed.
To copy the contents of the Nonvolatile Data Registers into the Volatile Data Registers, the Master must first initiate a
Start condition followed by the AT30TSE752A/754A/758A device address byte (1001AAA0 where “AAA” corresponds to
the hard-wired A
2-0
address pins). After the AT30TSE752A/754A/758A has received the proper address byte, the device
will send an ACK to the Master. The Master must then send the command byte of B8h for the Copy Nonvolatile Registers
to Volatile Registers operation. After the command byte of B8h has been sent, the AT30TSE752A/754A/758A will send
another ACK to the Master. After the Master has subsequently issued a Stop or repeated Start condition, the
AT30TSE752A/754A/758A will begin the internally self-timed copy operation. The copy process will take place in a
maximum time of t
COPYR
during which time the NVRBSY bit in the Configuration Register will indicate that the nonvolatile
registers are busy. If the Master issues a repeated Start condition instead of a Stop condition, the
AT30TSE752A/754A/758A will abort the copy operation and the contents of the Volatile Data Registers will not be
changed.
The Copy Nonvolatile Registers to Volatile Registers command will be ignored and no operation will be performed under
the following conditions: the Nonvolatile Registers are already busy (the NVRBSY bit of the Configuration Register is in
the Logic 1 state), the Volatile and Nonvolatile Registers are currently locked (the RLCK bit of the Nonvolatile
Configuration Register is in the Logic 1 state), or the Volatile and Nonvolatile Registers are permanently locked down
(the RLCKDWN bit of the Nonvolatile Configuration Register is in the Logic 1 state). However, the device will still respond
with an ACK to indicate that it received the command byte even though the copy process will not be performed.
Command Opcode
Copy Nonvolatile Registers to Volatile Registers B8h 1011 1000
Copy Volatile Registers to Nonvolatile Registers 48h 0100 1000
SCL
SDA
Start
by
Master
ACK
from
Slave
ACK
from
Slave
Address Byte Command Byte
MSB MSB
1 2 3 4 5 6 7 8 9 1 2 3 4 5 6 7 8 9
1 0 0 1 A A A 0 0 C7 C6 C5 C4 C3 C2 C1 C0 0