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1 status register, 2 configuration register – Rainbow Electronics LM95221 User Manual

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2.0 LM95221 Registers

(Continued)

2.1 STATUS REGISTER

(Read Only Address 02h):

D7

D6

D5

D4

D3

D2

D1

D0

Busy

Reserved

RD2M

RD1M

0

0

0

0

0

Bits

Name

Description

7

Busy

When set to "1" the part is converting.

6-2

Reserved

Reports "0" when read.

1

Remote diode 2 missing (RD2M)

Remote Diode 2 is missing. (i.e. D2+ shorted to V

DD

, Ground or D2-,

or D2+ is floating). Temperature Reading is FFE0h which converts to

255.875 ˚C if unsigned format is selected or 8000h which converts to

–128.000 ˚C if signed format is selected.

0

Remote diode 1 missing (RD1M)

Remote Diode 1 is missing. (i.e. D1+ shorted to V

DD

, Ground or D1-,

or D1+ is floating). Temperature Reading is FFE0h which converts to

255.875 ˚C if unsigned format is selected or 8000h which converts to

–128.000 ˚C if signed format is selected.

2.2 CONFIGURATION REGISTER

(Read Address 03h /Write Address 03h):

D7

D6

D5

D4

D3

D2

D1

D0

0

RUN/STOP

CR1

CR0

0

R2DF

R1DF

0

Bits

Name

Description

7

Reserved

Reports "0" when read.

6

RUN/STOP

Logic 1 disables the conversion and puts the part in standby mode.

Conversion can be activated by writing to one-shot register.

5-4

Conversion Rate (CR1:CR0)

00: continuous mode 66ms, 15 Hz (typ)

01: converts every 200ms, 5 Hz (typ)

10: converts every 1 second, 1 Hz (typ)

11: converts every 3 seconds,

1

3

Hz (typ)

Note: typically a remote diode conversion takes 26 ms and local

conversion takes 14 ms.

3

Reserved

Reports "0" when read.

2

Remote 2 Data Format (R2DF)

Logic 0: unsigned Temperature format (0 ˚C to +255.875 ˚C)

Logic 1: signed Temperature format (-128 ˚C to +127.875 ˚C)

1

Remote 1 Data Format (R1DF)

Logic 0: unsigned Temperature format (0 ˚C to +255.875 ˚C)

Logic 1: signed Temperature format (-128 ˚C to +127.875 ˚C)

0

Reserved

Reports "0" when read.

Power up default is with all bits “0” (zero)

LM95221

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