DS620 Datasheet, PDF (14/15 Pages) Dallas Semiconductor – Low-Voltage, +-0.5°C Accuracy Digital Thermometer and Thermostat

DS620 Digital Thermometer and Thermostat
RX
TX
ACK
DS620 generates acknowledge.
30
TX
RX
xxxxxxx1b
Bus master writes to the configuration register putting
the DS620 back in 1SHOT mode: 1SHOT = 1.
31
TX
RX
START Bus master generates a repeated start condition.
32
TX
RX
<address, 0> Bus master sends DS620 address, R/W = 0.
33
RX
TX
ACK
DS620 generates acknowledge.
34
TX
RX
48h
Master sends COPY DATA command to DS620 to
copy data in from SRAM memory to EEPROM memory.
35
RX
TX
ACK
DS620 generates acknowledge.
36
TX
RX
START Bus master generates a repeated start condition.
37
TX
RX
<address, 0> Bus master sends DS620 address, R/W = 0.
38
RX
TX
ACK
DS620 generates acknowledge.
39
Bus master sends a STOP CONVERT command to
stop the DS620 from continuously converting
temperature. NOTE: Bus master should ensure that
TX
RX
22h
EEPROM copy operation is complete before executing
40
the STOP CONVERT command by either waiting 10ms
from the time of the COPY DATA command or
checking the NVB bit in configuration register
RX
TX
ACK
DS620 generates acknowledge.
41
Bus master sends STOP condition to end
TX
RX
STOP
communication with DS620. (The bus master could
send a repeated start condition if additional
42
communication with the DS620 is desired.)
WRITING THE 1SHOT BIT COMMAND SEQUENCE
Configuring from continuous mode to 1SHOT mode.
BUS
MASTER
MODE
TX
TX
RX
TX
RX
TX
TX
RX
TX
RX
TX
RX
TX
TX
RX
TX
DS620
MODE
RX
RX
TX
RX
TX
RX
RX
TX
RX
TX
RX
TX
RX
RX
TX
RX
DATA
(MSB FIRST)
START
<address, 0>
ACK
51h
ACK
START
<address, 0>
ACK
ACh
ACK
xxxxxxx1b
ACK
START
<address, 0>
ACK
48h
COMMENTS
Bus master initiates a START condition.
Bus master sends DS620 address, R/W = 0.
DS620 generates acknowledge bit.
Master sends START CONVERT command to DS620
to start temperature conversions.
DS620 generates acknowledge bit and begins
conversions.
Bus master generates a repeated start condition.
Bus master sends DS620 address, R/W = 0.
DS620 generates acknowledge.
Bus master sends the address location of the MSb of
the configuration register (contains the 1SHOT bit).
This writes to the SRAM location corresponding the
EEPROM location.
DS620 generates acknowledge.
Bus master writes to the configuration register putting
the DS620 in 1SHOT mode: 1SHOT = 1.
DS620 generates acknowledge.
Bus master generates a repeated start condition.
Bus master sends DS620 address, R/W = 0.
DS620 generates acknowledge.
Master sends COPY DATA command to DS620 to
copy data in from SRAM memory to EEPROM
memory.
SEQUENCE
NUMBER
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
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