Freescale/NXP MPC5606B: eMIOS0 CTU ADC0 Program

While performing normal conversions on a few standard ADC channel inputs, use the Cross Triggering Unit (CTU) to trigger a conversion from an eMIOS channel event, where the channel is configured as Single Action Input Capture (SAIC).

In this example,

- ADC inputs ANS1 and ANS2 are continuously scanned.
- EMIOS and the CTU are configured so an input signal on eMIOS channel 2 will cause an event that "cross trigger" a conversion for ANS0.
- To generate an input signal, eMIOS channel 3 is configured for OPWM.
- Both channels use eMIOS channel 23 configured as modulus counter for their time base.

- Make the connections shown below. Connect ANS0 to a potentiometer or a known voltage.
- Connect ANS1:2 to other known voltages.
- Verify the eMIOS channel 2 injects an ADC command which reads the pot value.

Program Outcome:
              INPUT                  =>  OUTPUT 
ANS0 PB[8]  (CTU Inject Mode) (ADC0) =>  LED1 (ON if Input>=500, else OFF) 
ANS1 PB[9]  (Normal Scan mode)(ADC0) =>  LED2 (ON if Input>=500, else OFF) 
ANS2 PB[10] (Normal Scan mode)(ADC0) =>  LED3 (ON if Input>=500, else OFF) 

Switch4 PE[3]       =>  LED4 (ON if SW4 Pressed, else OFF)   
>[To Check Whether Program is executing in Infinite Loop] 

eMIOS0_3 PA[3] Generates 1KHz with 25% Duty Cycle 
eMIOS0_2 PA[2] injects conversion at ANS0 (ADC0). (CTU is used)

26/03/2016: Bug:Phase lag of 1uSec is present between (eMIOS0_1,2,3) and (eMIOS0_4,5,6)
26/03/2016: Bug:Phase lag of 1uSec is present between (eMIOS0_1,2,3) and (eMIOS0_4,5,6) 
01/04/2016: Phase lag removed. [clear the GTBE bit at beginning of Init_eMIOS() and set it at the end of the Init_eMIOS().] 18/04/2016: Remove PCTL[32]&PCTL[68] command from InitModesAndClks function   to run eMIOS and ADC together

                                               100 144  176
ANS0      32          B8      PCR[24]=2000     39 53   R9
ANS1      33          B9      PCR[25]=2000     38 52   T9
ANS2      34          B10     PCR[26]=2000     40 54   P9
eMIOS0[2] -           A2      PCR[2]=0503       5  9   F2
eMIOS0[3] -           A3      PCR[3]=0600      68 90   K15     

Connect Jumper between PA[2] and PA[3]

LED No. => Port No. => Pad No. => Pin No.(144-pin LQFP package)
LED1    => PE[4]    => PCR[68] => PIN 132
LED2    => PE[5]    => PCR[69] => PIN 133
LED3    => PE[6]    => PCR[70] => PIN 139
LED4    => PE[7]    => PCR[71] => PIN 140

SWITCH No. => Port No. => Pad No. => Pin No.(144-pin LQFP package)
SWITCH1    => PE[0]    => PCR[64] => PIN 10
SWITCH2    => PE[1]    => PCR[65] => PIN 12
SWITCH3    => PE[2]    => PCR[66] => PIN 128
SWITCH4    => PE[3]    => PCR[67] => PIN 129

Testing:- Output PWM waveform can be observed on DSO.


Click here to see more codes for Freescale/NXP MPC56xx Family.

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Thanks and Regards,
-Akshay P. Daga
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