MAX1455CSLASHD datasheet(18/25 Pages) MAXIM

18 / 25 page

Communication Command Examples

A selection of examples of the command sequences for

various functions within the MAX1455 follows.

Example 1. Change the baud rate setting and check com-

munications. If the communication with the MAX1455 is

lost due to a system baud rate change before sending the

reinitialization command, apply a power reset to guaran-

tee the initialization condition:

Example 2. Read the lookup table pointer (Temp-Index):

Example 3. Enable BDR measurement on OUT pin for

3.4s duration with 9600 baud rate:

Example 4. Write 8C40hex to the FSODAC register:

Example 5. Write 8C40hex to the FSODAC lookup

table location at Temp-Index 40. This example uses the

page erase command to clear the relevant section of the

EEPROM and assumes that none of the existing data in

that section is required to be kept:

COMMAND

ACTION

FFhex

Reinitialize part ready for baud rate learning.

Change system baud rate to new value.

01hex

Learn baud rate.

F8hex

Load 15 (Fhex) to IRSP[3:0] register.

59hex

Read IRS.

Host computer must be ready to receive data

on the serial line within 1 (baud rate) byte

time of sending the Read IRS command. The

MAX1455 returns CAhex. (IRSP values of

10 to 15 are configured to return CAhex for

communication checking purposes.)

COMMAND

ACTION

78hex

Load 7 to IRSP[3:0] register.

59hex

Read IRS.

Host ready to receive data within 1 byte

time of sending the Read IRS command.

The MAX1455 returns the current Temp-

Index pointer value.

COMMAND

ACTION

1Bhex

Load 1 (BDR measurement) to ALOC[3:0]

CAhex

Load 12 to the ATIM[3:0] register: (212+1) 5

8/9600 = 3.4s.

69hex

RdAlg.

The DIO pin is three-stated and the OUT pin

is connected internally to the BDR pin for a

duration of approximately 3.4s.

COMMAND

ACTION

00hex

Load 0 hex to the DHR[3:0] register.

41hex

Load 4 hex to the DHR[7:4] register.

C2hex

Load C hex to the DHR[11:8] register.

83hex

Load 8 hex to the DHR[15:12] register.

36hex

Load 3 (FSODAC) to the ICRA[3:0] register.

09hex

Ld ICR.

8C40 hex is written to the FSODAC register.

COMMAND

ACTION

A6hex

Load Ahex (page number corresponding to

EEPROM locations 280hex and 281hex) to

the IEEA[3:0] register.

79hex

Page Erase command.

Wait 7.1ms before sending any further

commands.

06hex

Load 0hex to the IEEA[3:0] register.

87hex

Load 8hex to the IEEA[7:4] register.

28hex

Load 2hex to the IEEA[9:8] (IRSP[3:0])

00hex

Load 0hex to the DHR[3:0] register.

41hex

Load 4hex to the DHR[7:4] register.

19hex

Write EEPROM. 40hex is loaded to

EEPROM address 280hex, which is the low

byte location corresponding to a Temp-Index

pointer value of 40.

16hex

Load 1 to the IEEA[3:0] register. IEEA[7:4]

and IEEA[9:8] already contain 8 and 2,

respectively.

C0hex

Load Chex to the DHR[3:0] register.

81hex

Load 8hex to the DHR[7:4] register.

19hex

Write EEPROM. 8Chex is loaded to

EEPROM address 281hex, which is the high

byte location corresponding to a Temp-Index

pointer value of 40.

MAX1455

Low-Cost Precision Sensor Signal Conditioner

www.maximintegrated.com

Maxim Integrated │ 18

MAX1455C/D Datasheet(PDF) 18 Page - Maxim Integrated Products

MAX1455C/D Datasheet(HTML) 18 Page - Maxim Integrated Products

Html Pages

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25

Datasheet Download

Link URL