LPC1769 QEI Help

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LPC1769 QEI Help

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lpcware
NXP Employee
NXP Employee
Content originally posted in LPCWare by PH.RAYMOND on Sun Apr 06 02:09:26 MST 2014
Dear all,
I am using an optical encoder with PHA PHB 256 steps.
QEIMAXPOS register is set to 0xff. Trial done also with  QEIMAXPOS register set to 0xf.
QEIPOS register is incrementing/decrementing correctly and resetting when overflow/underflow.

According to §26.6.3.6 of the UM10360 INXCNT is incrementing/decrementing during QEIPOS overflow/underflow.

Problem: INXCNT register remains to 0.

LPC1769 is a revA.
QEI Interrupt is disabled.

Index pin left as GPIO In a second time was set as Index input connected to GND with INVINX to 0 or to1.

Thanks in advance for help
Ph.RAYMOND

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lpcware
NXP Employee
NXP Employee
Content originally posted in LPCWare by PH.RAYMOND on Mon Apr 07 09:07:57 MST 2014
Thanks for your reply.
I will extract and post the corresponding code from my application.
For your information I am using LPCXpresso IDE in debug mode. After multiple encoder rotation, I do Run, Suspend , and look at the QEI peripheral.  IDXCNT register value is always 0 . I hope I am not facing an IDE problem!
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lpcware
NXP Employee
NXP Employee
Content originally posted in LPCWare by rocketdawg on Mon Apr 07 06:45:31 MST 2014
how can we help?  you will have to show the code.
have you checked LPCOpen?  there is sample code.
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