Instant Interrupts - Revisited

[HankMcSpank]

Just wondering if doing something like this is a 'no no' wrt to the interrupt handlers...

CPM1_Interrupt_Handler:

@ INT_DISABLE  CMP1_INT
[do some stuff here]
@ INT_ENABLE  CMP2_INT

@ INT_RETURN


CPM2_Interrupt_Handler:

@ INT_DISABLE  CMP2_INT
[do some stuff here]
@ INT_ENABLE  CMP1_INT

@ INT_RETURN

....essentially 'toggling' between each comparator being 'interrupt' enabled (& where the other comparator enables/disables itself & its partner). I'm getting weird results, but that's probably cos the rest of my code isn't robust - but just wanted to establish if it's ok to do this (especially if the comparators are interrupting rapidly due to them both rx'ing a rapidly changing input - and also each comparator potentially interrupting very closely in time)

Also, not having a clue about this kinda stuff, just wondering what's going on 'under the hood' so to speak....ie when an interrupt enable &/or disable is actioned as per the above? (does enabling/disabling in such a manner use a lot of processor clock cycles? Or is it pretty swift?)

Thanks.

[Darrel Taylor]

Nothing wrong there.

There are two different actions that can change the way INT_ENABLE works with version 1.10.

DEFINE INT_ENABLECLEARFIRST 1 ; (default)
With the above define, which is also the default, whenever you INT_ENABLE, the flag is automatically cleared before the interrupt is enabled.

DEFINE INT_ENABLECLEARFIRST 0
Whith this define, the flag is NOT cleared.
This can dramatically change the results and cause immediate interrupts if the flag is already set.

If INT_ENABLECLEARFIRST is 0, then INT_ENABLE takes one instruction cycle.
If INT_ENABLECLEARFIRST is 1, then INT_ENABLE takes two instruction cycles.

INT_DISABLE always takes one instruction.

[reik6149]

hi all, i face a problem here.

why when im trying to compile the dt_ints-18 file without changing anything, it shows

Error[113] c:\picbas~1.47\pbppic18.lib 1170 : symbol not previously defined (int_entry_H)

im using 18f2680

[Ioannis]

I suppose you did commend the 4 lines starting with __CONFIG in the xxx.inc file inside your PBP directory, right?

Ioannis

[reik6149]

huh?? do you means 18f2680.inc ? but i dint change anything with it..below is the inc file

;************************************************* ***************
;* 18F2680.INC *
;* *
;* By : Leonard Zerman, Jeff Schmoyer *
;* Notice : Copyright (c) 2006 microEngineering Labs, Inc. *
;* All Rights Reserved *
;* Date : 06/05/06 *
;* Version : 2.47 *
;* Notes : *
;************************************************* ***************
NOLIST
ifdef PM_USED
LIST
"Error: PM does not support this device. Use MPASM."
NOLIST
else
LIST
LIST p = 18F2680, r = dec, w = -311, w = -230, f = inhx32
INCLUDE "P18F2680.INC" ; MPASM Header
__CONFIG _CONFIG1H, _OSC_XT_1H
__CONFIG _CONFIG2H, _WDT_ON_2H & _WDTPS_512_2H
__CONFIG _CONFIG3H, _MCLRE_ON_3H & _PBADEN_OFF_3H
__CONFIG _CONFIG4L, _XINST_OFF_4L & _LVP_OFF_4L
NOLIST
endif
LIST
EEPROM_START EQU 0F00000h
BLOCK_SIZE EQU 64

[ScaleRobotics]

That is awesome, just opened a ton of possibilities with the speed of ASM, and the ease of DT_INTS and N-Bit Math. Thanks Darrel!

[HankMcSpank]

Just a quickie, re IOC interrupts....how do I know which one to use? (previously I was using IOC with a 16f690 & used RABC_INT then, but the PIC I'm using now doesn't have a PORT B)

From DT's site...

Several new interrupt sources have been added in version 1.00. GPC_INT, IOC_INT, RAC_INT, RABC_INT and the original RBC_INT are all forms of Port Change Interrupts. The chip being programmed determines which one you need to use.

Where do I look to establish this info?

I'm using one of the newer 14 pin 16F1823 PICs.

[Darrel Taylor]

The key is to look in the INTCON register.

For the 16F690, INTCON.0 is RABIF. So you would use RABC_INT.

With the 16F1823, INTCON.0 is IOCIF, so it's IOC_INT.

I could probably make it so IOC_INT works for all of them.
They are all "Interrupt On Change".

[DaTiNs]

Hello good people,


I follow this forum for a long time, it is excellent! I found a lot of good stuff on it.


Now I have a problem with the code from Mr. Darrel Taylor.


Thus, I use pic18f2550 and connect DS1307z and 4 PWM channels to PORTA


SDA Var PORTA.1
SCL Var PORTA.0


ASM
SPWM_LIST macro
SPWM_PIN PORTA, 2, _CH1
SPWM_PIN PORTA, 3, _CH2
SPWM_PIN PORTA, 4, _CH3
SPWM_PIN PORTA, 5, _CH4
endm
SPWM_INIT SPWM_LIST


INT_LIST macro
INT_Handler TMR1_INT, SPWMhandler, ASM, yes
endm
INT_CREATE
ENDASM
@ INT_ENABLE TMR1_INT


Now i got problem with this configuration. When i enable SPWM_LIST then RTC stop working, in fact he working but value he give, its not good. When i disable software pwm, RTC is working good.


I hope that you understande what is my problem and that one of you has a solution for this problem.


Sory for my english


Thanks a lot, Damir

[Darrel Taylor]

Do you have this in your program ... ?

ADCON1 = 15

[ScaleRobotics]

hi all, i face a problem here.

why when im trying to compile the dt_ints-18 file without changing anything, it shows

Error[113] c:\picbas~1.47\pbppic18.lib 1170 : symbol not previously defined (int_entry_H)

im using 18f2680

It's not really clear, but it sounds like you might be trying to compile the include file, rather than including it in your code. You are supposed to compile something like this:

LED1   VAR  PORTB.1

INCLUDE "DT_INTS-18.bas"     ' Base Interrupt System
INCLUDE "ReEnterPBP-18.bas"     ' Include if using PBP interrupts

ASM
INT_LIST  macro    ; IntSource,        Label,  Type, ResetFlag?
        INT_Handler   TMR1_INT,  _ToggleLED1,   PBP,  yes
    endm
    INT_CREATE               ; Creates the interrupt processor
ENDASM

T1CON = $31                ; Prescaler = 8, TMR1ON
@ INT_ENABLE  TMR1_INT     ; enable Timer 1 interrupts

Main:
  PAUSE 1
GOTO Main

'---[TMR1 - interrupt handler]--------------------------------------------------
ToggleLED1:
     TOGGLE LED1
@ INT_RETURN

[reik6149]

yea !! it works !!!! thank you very much ! im too busy body and trying to compile the file each of it.zzzz

[HankMcSpank]

Nothing wrong there.

There are two different actions that can change the way INT_ENABLE works with version 1.10.

DEFINE INT_ENABLECLEARFIRST 1 ; (default)
With the above define, which is also the default, whenever you INT_ENABLE, the flag is automatically cleared before the interrupt is enabled.

DEFINE INT_ENABLECLEARFIRST 0
Whith this define, the flag is NOT cleared.
This can dramatically change the results and cause immediate interrupts if the flag is already set.

If INT_ENABLECLEARFIRST is 0, then INT_ENABLE takes one instruction cycle.
If INT_ENABLECLEARFIRST is 1, then INT_ENABLE takes two instruction cycles.

INT_DISABLE always takes one instruction.

thanks for the clarification Darrel!

I look forward to the day where I don't have to read something 10 times ...and still not be 100% sure what it means! Until then please humour me - I'm using V1.1 of your interrupts ...when you mention the default is for your code to clear any interrupt flag (ie prior to enabling) , but then I got confused when seeing this accompanying snippet....

DEFINE INT_ENABLECLEARFIRST 1 ; (default)

So, Pop quiz, should I....

a) should I be putting such a line at the top of my program?
B) modifying DT_INTS-14.BAS?
c None of the above (it's erhm..... done by default!)

thanks!

[reik6149]

finally i could done with the code, hereby special thanks to darrel taylor and scalerobotics !!!

[ScaleRobotics]

Hey Darrel, I have a question about N-Bit math as it relates to DT_INTS ASM type interrupt.

Would the ASM part of the N-Bit Math qualify as an assembly interrupt? for instance, can I do math like this in the middle of an asm type interrupt handler, without having to worry? I am not really talking about this code (your degree conversion example) but doing math like this inside an assembly interrupt handler. Or since it is using an include file, I have to worry?

   ASM
     MOVE?WP  _degree_Total, _Temp1           ; copy degrees to a PVAR
     MOVE?CP  65535, _Temp2                   ; put multiplier in a PVAR
     MATH_MUL _Temp1, _Temp2, _Temp1          ; Temp1 = DEG * 65535
     MOVE?CP  35999, _Temp2
     MATH_DIV _Temp1, _Temp2, _Temp1          ; Temp1 = Temp1 / 35999 (16-bit result)
     MOVE?PP  _Temp1, _Temp2                  ; copy result to Temp2
     MATH_ROR _Temp2                          ; rotate right 4 times
     MATH_ROR _Temp2
     MATH_ROR _Temp2
     MATH_ROR _Temp2                          ; Temp2 is now 12-bits
     MOVE?PW  _Temp1, _Decimal_value_16bit    ; copy PVAR's to WORDs
     MOVE?PW  _Temp2, _Decimal_value_12bit
   ENDASM

Thanks,

Walter

[Darrel Taylor]

> Would the ASM part of the N-Bit Math qualify as an assembly interrupt?
Absolutely!

The math routines don't use any of PBP system variables.
But they do use an FSR, so that must be saved/restored at the beginning/end of the ISR.

There are two macro's included in N-Bit_Math that do the FSR save/restore ...

@ FSRSAVE
; -- math code here --
@ FSRREST

ADD: DT_INTS already saves/restores the FSR's, so if you're using DT_INTS, there's nothing to worry about.

hth,

[Ioannis]

I downloaded the latest version 1.10 for the DT-INTS14 and now I get a lot of errors.

Does anyone else has the same problem? With v1.0 had no error (but nothing was working either.... )

I want to use IOC of a F887 device.

The test code is this:

DEFINE OSC 4

;----- Configuration bits ------------------------------------------------
@Line1 = _DEBUG_OFF & _LVP_OFF & _FCMEN_OFF & _IESO_OFF & _BOR_OFF
@Line2 = _CP_OFF & _MCLRE_ON & _PWRTE_ON & _WDT_ON & _XT_OSC

@ __CONFIG _CONFIG1, Line1 & Line2
@ __CONFIG _CONFIG2, _WRT_HALF & _BOR40V

OPTION_REG.0=1		'PSA0 PRESCALER SELECT 1:1 TO 1:256
OPTION_REG.1=1		'PSA1
OPTION_REG.2=1		'PSA2
OPTION_REG.3=1		'PRESCALER TO: 1->WDT, 0->TMR0
OPTION_REG.4=0		'T0SE SOURCE EDGE 1->H TO L, 0->L TO H
OPTION_REG.5=0		'T0CS 1->FROM RA4, 0->FROM INT. CLOCK
OPTION_REG.6=0		'INT EDGE SELECT 0->H TO L, 1->L TO H
OPTION_REG.7=0		'PULL UP 1->DISABLE, 0->ENABLE

adcon0=%01000001    '0 off
adcon1=$80'6 off (all digitals)
ansel=$01
anselh=$00

PORTA=%00000001:PORTB=%00010000:PORTC=%10000001:PORTD=0:PORTE=0

TRISC=$80:TRISD=0:TRISE=0

TRISA = %00000001:TRISB = %00010000

WPUB=%00010000          'Enable weak pull up on PortB.4

while 1
wend

ASM
INT_LIST  macro;    IntSource,  Label,      Type,  ResetFlag?
    INT_Handler     RBC_INT,    _IOC2,      PBP,    yes
    endm
    INT_CREATE            ; Creates the interrupt processor
ENDASM

@   INT_ENABLE  RBC_INT      ; Enable Port B on change
'-------------   INTERRUPTS SETUP   ---------------------

IOC2:
    if portb.4=1 then
        high portb.0
    else
        low portb.0
    endif
@ INT_RETURN

The errors are like ERROR: (" Add:" wsave1 VAR BYTE $A0 SYSTEM, Or change to wsave BYTE $70 SYSTEM)

or

ERROR: (Chip has RAM in BANK3, but wsave3 was not found.) etc

Ioannis

[Darrel Taylor]

Everyone seems to do that.....

What you need to do is contained in the error messages.
Follow the directions, and they will go away.

[Ioannis]

Sorry I did not fully understood what you mean...

With the old (version 1.00) there is no problem in compiling with RBC_INT interrupt. With 1.10 I get various errors like the ones posted.

Of course I made a mistake in interrupt selection. IOC_INT should be used and not RBC_INT.

With the old version 1.00, after compiling I get

ERROR: ("INT_Handler" - Interrupt Flag (INTCON,IOCIF ) not found.)

and

ERROR: ("INT_ENABLE" - Interrupt Flag (INTCON,IOCIF ) not found.)

Ioannis

[ScaleRobotics]

Hey Iannis,

This may be a dumb question, but are you including the includes? I don't see them in your code.

if you are getting the wsave, wsave1, wsave2, or wsave3 errors, change the wsave settings in the DT_INTS-14.bas, like it shows you.

[Ioannis]

Hi. Yes I did included them. The sample was stripped down from the obvious.

Well, the new DT-INTs have changed a little I suppose.

OK, Darrel pointed what to do. I did uncomment the wsave1,2,3 lines and put on the main program the lines:

wsave   VAR BYTE    $20     SYSTEM      ' location for W if in bank0
;wsave   VAR BYTE    $70     SYSTEM      ' alternate save location for W 
                                         ' if using $70, comment wsave1-3

It seems that it doesn't matter which one I un-comment as it compiles both.

But with version 1.10 of the DT-INTs I have a new error about the INTCON,IOCIF flag...

Ioannis