Rainbow-electronics DS2422 Manual do Utilizador descarregar pdf (Página 12)

DS2422/DS2423

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MEMORY FUNCTION EXAMPLE (DS2423)

Example: Write two data bytes to memory location 0026 and 0027. Read entire memory.

MASTER MODE DATA (LSB FIRST) COMMENTS

TX Reset Reset pulse (480-960 µs)

RX Presence Presence pulse

TX CCh Issue “skip ROM” command

TX 0Fh Issue “write scratchpad” command

TX 26h TA1, beginning offset=26h

TX 00h TA2, address=0026h

TX <2 data bytes> Write 2 bytes of data to scratchpad

TX Reset Reset pulse

RX Presence Presence pulse

TX CCh Issue “skip ROM” command

TX AAh Issue “read scratchpad” command

RX 26h Read TA1, beginning offset=26h

RX 00h Read TA2, address=0026h

RX 07h Read E/S, ending offset=7h, flags=0h

RX <2 data bytes> Read scratchpad data and verify

TX Reset Reset pulse

RX Presence Presence pulse

TX CCh Issue “skip ROM” command

TX 5Ah Issue “copy scratchpad” command

TX 26h

TX 00h

TX 07h

TA1

TA2 AUTHORIZATION CODE

E/S

TX Reset Reset pulse

RX Presence Presence pulse

TX CCh Issue “skip ROM” command

TX F0h Issue “read memory” command

TX 00h TA1, beginning offset=0

TX 00h TA2, address=0000h

RX <512 bytes> Read entire memory

TX Reset Reset pulse

RX Presence Presence pulse, done

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Rainbow-electronics DS2422 Manual do Utilizador Página 12