Rainbow Electronics DS2422 - Manual (Page 13)

DS2422/DS2423
13 of 25
MEMORY FUNCTION EXAMPLE (DS2423)
Read page 14 and counts of Input A. Rewrite page 14 with 32 bytes. Read Memory + Counter, Write
Scratchpad, Copy Scratchpad.
MASTER MODE DATA (LSB FIRST) COMMENTS
TX Reset Reset pulse (480-960 µs)
RX Presence Presence pulse
TX CCh Issue “skip ROM” command
TX A5h Issue “read memory + counter” command
TX C0h TA1, beginning offset=C0h
TX 01h TA2, address=01C0h
RX <32 data bytes> Read 32 bytes of data
RX <4 data bytes> Read Counts of Input A
RX <4 data bytes> Read 32 Zero Bits
RX <2 data bytes> Read (inverted) CRC16
TX Reset Reset pulse
RX Presence Presence pulse
TX CCh Issue “skip ROM” command
TX 0Fh Issue “write scratchpad” command
TX C0h TA1, beginning offset=C0h
TX 01h TA2, address=01C0h
TX <32 data bytes> Read 32 bytes of data to scratchpad
RX <2 data bytes> Read (inverted) CRC16
TX Reset Reset pulse
RX Presence Presence pulse
TX CCh Issue “skip ROM” command
TX 5Ah Issue “copy scratchpad” command
TX C0h
TX 01h
TX 1Fh
TA1
TA2
AUTHORIZATION CODE
E/S
RX <1 data byte> Read Copy Scratchpad response
TX Reset Reset pulse
RX Presence Presence pulse, done