1.13.3 Rocker Switches

Eight rocker switches (SW5) are provided for user application development. These switches are active low and input a logic low when set to the closed position. There are no external pullups on these switches so the internal pullups should be enabled on the MCU port pins to ensure proper operation. Port A pins can be disconnected from the rocker switches by removing the appropriate jumper. The rocker switches are connected as described below

Table 1-10 Rocker Switch (SW5) Connections

Switch

MCU Port

Jumper

 

 

 

1

PTA0

J24

 

 

 

2

PTA1

J25

 

 

 

3

PTA2

J26

 

 

 

4

PTA3

J27

 

 

 

5

PTA4

J28

 

 

 

6

PTA5

J29

 

 

 

7

PTA6

J30

 

 

 

8

PTA7

J31

 

 

 

1.13.4 Accelerometer

A Freescale MMA6270QT accelerometer (U5) is provided to assist users in developing accelerometer based application code. The MMA6270QT provides output data in the X and Y direction and has a sleep mode. The MMA6270QT is a 3.3V part and is connected to the MC9S08AC60 through the use of a level translator. The X and Y outputs are connected back to the MCU both directly from the accelerometer (3.3V signals) and amplified to 5V through the use of op-amps. The sleep mode is an active low input to the accelerometer. When a logic low is applied to the sleepmode pin the device outputs are turned off, providing significant reduction of operating current (low to 3 uA typically). The MCU port pins can be disconnected from the accelerometer by removing the appropriate jumper. The accelerometer is connected as described below

DEMO9S08AC60E User’s Guide, Rev. 0.1

Freescale Semiconductor

19

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Image 19
Freescale Semiconductor DEMO9S08AC60E manual Rocker Switches, Rocker Switch SW5 Connections, Accelerometer