DS2770

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Write Data [6Ch, XX].

This command writes data to the DS2770 starting at memory address XX. The

LSb of the data to be stored at address XX can be written immediately after the MSb of the address has

been entered. Because the address is automatically incremented after the MSb of each byte written, the

LSb to be stored at address XX+1 can be written immediately after the MSb to be stored at address XX. If

the bus master continues to write beyond address FFh, the DS2770 will start over-writing at address 00h.

Writes to read-only addresses, reserved addresses, and locked EEPROM blocks are ignored. Incomplete

bytes are not written. Writes to unlocked EEPROM blocks are to shadow RAM rather than EEPROM.

See the Memory section for more details.

Copy Data [48h, XX].

This command copies the contents of shadow RAM to EEPROM for the

EEPROM block beginning with address XX (20h for block 0, 30h for block 1, and 40h for block 2). Copy

Data commands that address locked blocks are ignored. While the Copy Data command is executing, the

EEC bit in the EEPROM Register is set to 1 and writes to EEPROM addresses are ignored. Reads and

writes to non-EEPROM addresses can still occur while the copy is in progress. The Copy Data command

Recall Data [B8h, XX].

This command recalls the contents of the EEPROM block containing the first

address location found in the block to shadow RAM.

Lock [6Ah, XX].

This command locks (write-protects) blocks of EEPROM whose first memory location

is XX (20h for block 0, 30h for block 1, and 40h for block 2). The Lock bit in the EEPROM Register

must be set to 1 before the Lock command is executed. The Lock command must be the next command

issued (after the 1-Wire reset) once the Lock bit has been set. If the Lock bit is 0, the Lock command has

no effect. The Lock command is permanent; a locked block can never be written again. The Lock

Refresh [63h].

The Refresh command restores the Status Register initialization data stored in address

location 31h to the Status Register. The Status Register is initialized directly from the EEPROM and not

from the shadow RAM.

Start Charge [B5h].

The Start Charge command is used to initiate charge through the host interface.

Stop Charge [BEh].

The Stop Charge command is used to terminate charge through the host interface.