Sensors

10

Freescale Semiconductor

MMA690xQ

Figure 2-2 DSP Input Multiplexor Verification Flow Chart (Y Axis)

2.1.4

Temperature Sensor Value (TEMP)

This read-only register contains a signed value which provides a relative temperature indication. The temperature sensor is

uncalibrated and its output for a given temperature will vary from one device to the next. The value in this register increases with

temperature.

2.1.5

Device Status Register (DEVSTAT)

This read-only register is accessible in all modes.

2.1.5.1

Internal Data Error Flag (IDE)

This flag will be set if a register data parity fault or a marginally programmed fuse is detected. Device reset is required to clear

this fault condition. If a parity error is associated with the data stored in the fuse array, this fault condition cannot be cleared. This

flag is disabled when the device is in test mode.

2.1.5.2

Device Initialization Flag (DEVINIT)

This flag is set during the interval between negation of internal reset and completion of device initialization. DEVINIT is cleared

automatically.

Table 2-6. Temperature Sensor Value Register

Location

Bit Function

Address

Register

7

6

5

4

3

2

1

0

$0F

TEMP

TEMP[7]

TEMP[6]

TEMP[5]

TEMP[4]

TEMP[3]

TEMP[2]

TEMP[1]

TEMP[0]

Table 2-7. Device Status Register

Location

Bit Function

Address

Register

7

6

5

4

3

2

1

0

$10

DEVSTAT

IDE

0

DEVINIT

TF

0

0

0

DEVRES

YINV = 0, ST1 = 0, ST0 = 1

MULTIPLEXOR

Y

N

YINV = 0, ST1 = 1, ST0 = 1

YINV = 1, ST1 = 0, ST0 = 1

YINV = 1, ST1 = 1, ST0 = 1

Y

N

VERIFICATION

SUCCESSFUL

MULTIPLEXOR

VERIFICATION

FAILED