Example MPC5748G + PCF8885 Touch sensing demo GHS614

Document created by Lukas Zadrapa Employee on May 18, 2016Last modified by Diana Torres on Feb 24, 2017
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* Detailed Description:

* Sensor board OM11057A which includes two PCF8885 circuits is connected

* to MPC5748G via I2C. MPC5748G continuously reads the state of touch sensors

* and the state is shown on LED diodes which are driven by I2C circuit PCA9535.

*

* Used I2C driver: https://community.freescale.com/docs/DOC-330972

*

* Touch sensor board (page 9 and 10):

* http://www.nxp.com/documents/user_manual/UM10505.pdf

*

* ------------------------------------------------------------------------------

*

* Connection:

*

* Connect I2C bus (I2C_2 on MPC5748G) to sensor board:

* I2C_SCL: P24-33 (pin PE9) on MPC574XG-MB to K3-1 on OM11057A

* I2C_SDA: P24-35 (pin PE8) on MPC574XG-MB to K3-13 on OM11057A

* Note: use two pull-up resistors on I2C signals (pulled to 3.3V).

* The value should be 3k3 - 10k

*

* Connect power supply from MPC574XG-MB to OM11057A:

* GND: P24-2 on MPC574XG-MB to K3-7 on OM11057A

* 3.3V: P24-1 on MPC574XG-MB to K3-9 on OM11057A

*

* Connect SLEEP pins of both PCF8885 to GND (this will ensure that sleep mode

* is not entered):

* SLEEP1: K3-11 to K2-3 (both on OM11057A)

* SLEEP2: K1-6 to K1-8 (both on OM11057A)

*

* ------------------------------------------------------------------------------

* Sensor board:    OM11057A

*                  http://www.nxp.com/documents/user_manual/UM10505.pdf

* Test HW:         MPC574XG-324DS Rev.A + MPC574XG-MB Rev.C

* MCU:             PPC5748GMMN6A 1N81M

* Fsys:            160 MHz PLL

* Debugger:        Lauterbach Trace32

* Target:          internal_FLASH

*

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