Rainbow Electronics DS1904 - Manual (Page 5)

DS1904
5 of 12
CLOCK FUNCTION COMMAND FLOW CHART Figure 5
Master TX Control
Function Command
66H
Read Clock
?
Y
N
Bus Master
TX Reset
?
N
Y
N
Bus Master
TX Reset
?
DS1904 copies
RTC Counter
to R/W Buffer
99H
Write Clock
?
N
Y
Y
N
Bus Master
TX Reset
?
Bus Master TX
LS Byte (7:0)
Bus Master TX
next Byte (15:8)
Bus Master TX
next Byte (23:16)
Bus Master TX
MS Byte (31:24)
Bus Master TX
Device Control Byte
DS1904 copies
R/W Buffer
to RTC Counter
DS1904 TX
Presence Pulse
Bus Master RX
next Byte (15:8)
Bus Master RX
next Byte (23:16)
Bus Master RX
MS Byte (31:24)
Bus Master RX
LS Byte (7:0)
Bus Master RX
Device Control Byte
Y