DS620 Digital Thermometer and Thermostat

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COPYING TO EEPROM COMMAND SEQUENCE

Data is written to DS620 and then copied from SRAM to EEPROM

BUS

MASTER

MODE

DS620

MODE

DATA

(MSB

FIRST)

COMMENTS

SEQUENCE

NUMBER

TX

RX

START

Bus master initiates a START condition.

1

TX

RX

<address, 0> Bus master sends DS620 address, R/

W = 0.

2

RX

TX

ACK

DS620 generates acknowledge bit.

3

TX

RX

A4h

Bus master sends the address location of the first byte

of data to be written. (In this case the first byte of user

EEPROM).

4

RX

TX

ACK

DS620 generates acknowledge.

5

TX

RX

<data>

Bus master sends one byte of data to the SRAM

location for EEPROM address A4h.

6

RX

TX

ACK

DS620 generates acknowledge.

7

TX

RX

<data>

Bus master sends one byte of data to the SRAM

location for EEPROM for address A5h.

8

RX

TX

ACK

DS620 generates acknowledge.

9

TX

RX

<data>

Bus master sends one byte of data to the SRAM

location for EEPROM for address A6h.

10

RX

TX

ACK

DS620 generates acknowledge.

11

TX

RX

<data>

Bus master sends one byte of data to the SRAM

location for EEPROM for address A7h.

12

RX

TX

ACK

DS620 generates acknowledge.

13

TX

RX

START

Bus master generates a repeated start condition.

14

TX

RX

<address, 0> Bus master sends DS620 address, R/

W = 0.

15

RX

TX

ACK

DS620 generates acknowledge.

16

TX

RX

ACh

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. NOTE: Sequence numbers 17

through 23 need to be done only if DS620 is in 1SHOT

mode: 1SHOT = 1.

17

RX

TX

ACK

DS620 generates acknowledge.

18

TX

RX

xxxxxxx0b

Bus master writes to the configuration register putting

the DS620 in continuous conversion mode: 1SHOT =

0.

19

RX

TX

ACK

DS620 generates acknowledge.

20

TX

RX

START

Bus master generates a repeated start condition.

21

TX

RX

<address, 0> Bus master sends DS620 address, R/

W = 0.

22

RX

TX

ACK

DS620 generates acknowledge

23

TX

RX

51h

Master sends START CONVERT command to DS620

to start temperature conversions.

24

RX

TX

ACK

DS620 generates acknowledge bit and begins

conversions.

25

TX

RX

START

Bus master generates a repeated start condition.

26

TX

RX

<address, 0> Bus master sends DS620 address, R/

W = 0.

27

RX

TX

ACK

DS620 generates acknowledge.

28

TX

RX

ACh

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. NOTE: command sequence

numbers 29 through 34 need only be done if a return to

1SHOT mode operation is needed.

29