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Hello.

I have a PIC32MX170F256B FC8 project with 2 rotary encoders each using IOC. An IOC portA to read one and IOC portB to read the other but the portB interrupt don't work, tried all avail 2 pin combinations for the encoder on portB. Verified encoder is working.

Also tested FC8 with ONLY 1 interrupt = port B, same.

Tried a PIC32MX270F256B same result.

Lastly tried PIC24HJ128GP202 and this works perfectly with it's single IOC set to all 4 encoder pins.

Next looked at PIC32 C code with Port A interrupts set for A0 & A1; the change notice enable bits for A are in the CNENA register

CNENA = 0x83 | (0x7,<<8)) so this seems correct from the datasheet as "3" gives 1's for A1 & A0 (this register only requires the lowest 5 bits as there are only 5 pins on port A but 2 of these are for the crystal).

However for the other IOC on Port B

CNENB = 0x0 | (0x0,<<8)) so it is not setting any bits (showing 0x0 not 0x00?)

To try this only requires selecting the chip in FC8 adding a rotary encoder to port B and setting an IOC portB, so I haven't attached any code.

Could you have a look at this please as I am out of my depth?

regards

Paul McK

Hi Paul,

Thanks for letting us know, I've hopefully fixed it for you now via the update system.

Ben

Thanks. I tried this and the interrupts are now definitely recognised as demonstrated by the PIC rebooting every time the encoder is rotated left or right. I had a squiz at the c-code and saw CNENB = 0x60 | (0x0,<<8 which is now correct for interrupt on B5 or B6.

But what is "35" doing in

//Handler code for [IOC1]
#ifndef MX_ISR_CNB
#define MX_ISR_CNB
void __ISR(35, ipl2AUTO) _IntHandlerChangeNotification1(void)

instead of void_Change_Notice_Vector, ipl2AUTO) _IntHandlerChangeNotification1(void),

regards

Paul

Hi Paul,

That's a very good point, well spotted and thanks for letting us know. I need to investigate further on this one. The other vectos shown are for other interrupts and so won't be working as expected.

The appears to be a single vector for all three IOC interrupt types but three individual IRQ values so I need to try and get to the bottom of this. We might end up with a single interrupt for all Ports depending on how it's done on the other devices.

#define _CHANGE_NOTICE_VECTOR 34

#define _CHANGE_NOTICE_A_IRQ 45
#define _CHANGE_NOTICE_B_IRQ 46
#define _CHANGE_NOTICE_C_IRQ 47

Ben

FYI to give more context, this extract is from an encoder & touch screen test program with (2) IOC interrupts where only IOCB doesn't work properly plus (2) timer interrupts which both work, yet all (4) have a warning that the macros may not get called?


//Handler code for [IOC1]
#ifndef MX_ISR_CNB
#define MX_ISR_CNB
void __ISR(35, ipl2AUTO) _IntHandlerChangeNotification1(void)
{
PORTB;
IFS1bits.CNBIF = 0;
FCM_fine_encoder();
}
#else
#warning "This interrupt has previously been enabled, so the macro <fine_encoder> may never get called."
#endif


//Handler code for [IOC0]
#ifndef MX_ISR_CNA
#define MX_ISR_CNA
void __ISR(_CHANGE_NOTICE_VECTOR, ipl2AUTO) _IntHandlerChangeNotification0(void)
{
PORTA;
IFS1bits.CNAIF = 0;
FCM_coarse_encoder();
}
#else
#warning "This interrupt has previously been enabled, so the macro <coarse_encoder> may never get called."
#endif


//Handler code for [TMR3]
#ifndef MX_ISR_T3
#define MX_ISR_T3
void __ISR(_TIMER_3_VECTOR, ipl1AUTO) _IntHandlerDrvTmrInstance2(void)
{
IFS0bits.T3IF = 0;
FCM_printcount();
}
#else
#warning "This interrupt has previously been enabled, so the macro <printcount> may never get called."
#endif


//Handler code for [TMR2]
#ifndef MX_ISR_T2
#define MX_ISR_T2
void __ISR(_TIMER_2_VECTOR, ipl1AUTO) _IntHandlerDrvTmrInstance1(void)
{
IFS0bits.T2IF = 0;
FCM_Touch();
}
#else
#warning "This interrupt has previously been enabled, so the macro <Touch> may never get called."
#endif

regards

Paul

Ben

Forgot to add, if IOC B is enabled along with the timer interrupts, the PIC reboots on encoder CW or CCW rotation, but with the other encoder added as IOC A it works OK on that encoder but now when the IOC B encoder is operated nothing is read, the PIC freezes & doesn't reboot.

Paul