Sensors

Freescale Semiconductor, Inc.

39

MMA16xxKW

4.2.1.11

Format Control Command

The Format Control command is supported in the following command formats:

• Standard Long Command

• Enhanced Long Command as configured by the Format Control Command (Reference Section 4.2.1.11)

The device ignores the Format Control command if the command is in any other format. The device supports the Format Con-

trol command with the DSI Global Address of ‘0000’, but does not provide a response.

The format control registers defined in the DSI Bus Standard V2.5 are shown in Table 44. The reset values assigned to each

register are also indicated.

Table 40. Format Control Command

Data

Address

Command

CRC

D[7]

D[6]

D[5]

D[4]

D[3]

D[2]

D[1]

D[0]

A[3]

A[2]

A[1]

A[0]

C[3]

C[2]

C[1]

C[0]

R/W

FA[2]

FA[1]

FA[0]

FD[3]

FD[2]

FD[1]

FD[0]

A[3]

A[2]

A[1]

A[0]

1010

0 to 8 bits

Table 41. Format Control Command Bit Definitions

Bit Field

Definition

C[3:0]

Format Control Command = ‘1010’

A[3:0]

DSI device address. This field contains the device address. This field must match the internal programmed address field. Otherwise, the

command is ignored.

FD[3:0]

Data to be written to the Format Control Register addressed by FA[2:0] if the R/W bit is set to ‘1’.

FA[2:0]

The Address of the Format Control Register to read or written.

R/W

Read/Write determines if the register at address FA[2:0] is to be read or written.

1 - Write FD[3:0] to the Format Control Register addressed by FA[2:0]

0 - Read the Format Control Register addressed by FA[2:0]

Table 42. Long Response - Format Control Command

Response

CRC

D[15]

D[14]

D[13]

D[12]

D[11]

D[10]

D[9]

D[8]

D[7]

D[6]

D[5]

D[4]

D[3]

D[2]

D[1]

D[0]

A[3]

A[2]

A[1]

A[0]

0110

R/W

FA[2]

FA[1]

FA[0]

FD[3]

FD[2]

FD[1]

FD[0]

0 to 8 bits

Table 43. Format Control Response Bit Definitions

Bit Field

Definition

FD[3:0]

The contents of the Format Control Register addressed by FA[2:0].

FA[2:0]

The Address of the Format Control Register that was read or written.

R/W

Read/Write indicates if the register at address FA[2:0] was read or written.

1 - FD[3:0] contains the data written to the Format Control Register addressed by FA[2:0]

0 - FD[3:0] contains the contents for the Format Control Register addressed by FA[2:0]

A[3:0]

DSI device address. This field contains the device address.

Table 44. Format Control Register Values

Format Control Register

Register Address

Reset Values

DSI Standard Values

Definition

FA[2] FA[1] FA[0] FD[3] FD[2] FD[1] FD[0] FD[3] FD[2] FD[1] FD[0]

CRC Polynomial - Low Nibble

00000010001

CRC Polynomial - High Nibble

00100010001

Seed - Low Nibble

01010101010

Seed = ‘1010’

Seed - High Nibble

01100000000

CRC Length (0 to 8)

10001000100

CRC Length = 4

Short Word Data Length (8 to 15)

10110001000

Short Command Length = 8

Reserved

11000000000

N/A

Format Selection

11100000000

N/A