Instant Interrupts - Revisited

[vamtbrider]

I added the port configuration and acon register configs. That has an effect...
The bootloader never leaves the bootloader mode to run the user app.

if I comment out the Hardware configuration section and compile I can load the code via the bootloader, the device disappears from the USB list and then ~10seconds later I get the USB device not recognized.

I have reloaded the led test program just to make sure the bootloader and chip are still working and they are. Very puzzling, but the registers do seem to have an effect.

Nothing in the DT_INT writes to EEPROM 0x00? If there is a 5A there then the bootloader thinks its still in boot mode.

    LED1   VAR  PORTB.0
    
    DEFINE OSC 20          
    DEFINE RESET_ORG 0x800  
    
    INCLUDE "DT_INTS-18.bas"        ' Base Interrupt System
    INCLUDE "ReEnterPBP-18.bas"     ' Include if using PBP interrupts                                           

    '   Hardware configuration
    '   ======================    
        '
        '   I/O and PORTs
        '   -------------  
    PORTB   =   0
    PORTC   =   0
    PORTD   =   0
    PORTE   =   0
    TRISB   =   %00000000       '<2-1> Inputs
    TRISC   =   0
    TRISA   =   0
    TRISD   =   0
    TRISE   =   0
        '
        '   A/D converter
        '   -------------       
    ADCON0  =   %00000000       ' A/D converter off     
    ADCON1  =   %00001111       ' All Digital Inputs
 '   ADCON2  =   %00000000 
                           


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 10  
GOTO Main

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

Still puzzled...

[vamtbrider]

This hardware config give the same results as the original issue...ie the LED does not blink and the code appears to run off into la la land. Not sure how it is being detected as a usb device with the DT_INTS-18 code.

    '   Hardware configuration
    '   ======================    
        '
        '   I/O and PORTs
        '   -------------  
    PORTB   =   0
    PORTC   =   0
    PORTD   =   0
    PORTE   =   0
    TRISB   =   %11111110       '<7:1> Inputs
    TRISC   =   0
    TRISA   =   0
    TRISD   =   0
    TRISE   =   0
        '
        '   A/D converter
        '   -------------       
    ADCON0  =   %00000000       ' A/D converter off     
    ADCON1  =   %00001111       ' All Digital Inputs
    ADCON2  =   %00000000

I have two port b pins connected together as part of the ICSP and 2 others connected for inputs off a single PB. Setting the TRISB to FE is what got me back to the original problem.

[Bruce]

I've never used this loader, but I did take a quick peek at the source files.

Try this;

    DEFINE OSC 20          
    DEFINE RESET_ORG 0x800  
    
    INCLUDE "DT_INTS-18.bas"        ' Base Interrupt System
    INCLUDE "ReEnterPBP-18.bas"     ' Include if using PBP interrupts                                           

    LED1   VAR  PORTB.0
    
'   Hardware configuration
    '   ====================== 
    ADCON1  =   %00001111       ' All Digital Inputs                         


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 10  
GOTO Main

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

Remove power. Place a jumper from PORTE.0 to ground. Power up & load the above after compiling it.

After programming it with the loader, power down. Move the jumper on PORTE.0 to Vcc, and power up.

Does it work now?

[vamtbrider]

If I don't have the TRISB config the bootloader never enters the user program mode.

I added the TRISB = %1111110 and it enters the user program but still shows an undetected USB device after a few seconds and the LED on PORTB.0 is still not blinking.

One more piece of info, I am getting power from the USB port on my laptop. Even though the user program is not using USB I am "stealing" power for this test setup from the USB port. i.e. I download the program to the bootloader through the PIC USB and leave the cable connected to power the board for testing.

It doesn't look like anything in the DT_INTS would be triggered from activity on the USB port since I have not explicitly configured the USB_INT. The PIC is certainly seeing a request from the PC since its connected to the PIC circuitry and that could be why I get the USB device not recognized...although I don't get that when i am running just the Blink program using PAUSE 500 statements.

When I get home later tonight I will load this program directly on the PIC through the ICSP without the bootloader to verify my setup is happy. Then I will try the bootloader again and use an external power supply instead of the USB power.

ADDED: I have reconfigured the Bootloader to use PORT B.1 instead of Diolan's default of PortE.0. My end application will use Port B.1 so I built this test board assuming portb.1 would work.

[Darrel Taylor]

Try adding ...

DEFINE LOADER_USED 1

[Bruce]

Pheeeewwww! I do NOT like that loader at all.

I put one together for you here using the Microchip USB HID boot-loader. Give this one a shot. It works 100% with DT_INTS-18.

I modified the original C18 loader file so you can switch between the external crystal & internal osc at run-time to switch back-and-forth to various speeds.

Use a 20MHz crystal, 18F4550, and you should have no problems at all with the loader or DT_INTS-18.

Of course you'll need to download & install the Microchip HID USB loader PC app, but I find that one WAY nicer, and easier to use than the Diolan thing.

'****************************************************************
'*  Name    : USB_TST.BAS                                       *
'*  Author  : B. Reynolds                                       *
'*  Notice  : Copyright (c) 2010 http://www.Rentron.com         *
'*          : All Rights Reserved                               *
'*  Date    : 3/25/2010                                         *
'*  Version : 1.0                                               *
'*  Notes   : Using the Microchip USB HID Boot-Loader with PBP  *
'*          : and DT_INTS.                                      *
'****************************************************************
    
   ' Using the Microchip MCHPFSUSB v2.1 HID USB Bootloader with PBP & DT INTS.
    
   ' Place a 10K pull-up on RB4 with a switch to ground RB4 when pressed. 
    
   ' Loader mode. Press & hold switch on RB4, then press/release reset switch on /MCLR.
   ' Now release switch on RB4.
    
   ' LEDs on PORTD.0 & D.1 will blink on/off quickly showiing you're in loader mode
   ' and the MCHPFSUSB v2.1 HID PC bootloader software should now recognize your board.
    
   ' Open & load your compiled code, with the loader software, then press/release
   ' the switch on /MCLR, or click Reset Device on the loader software.
   
   ' Your code should now be running. 
    
   DEFINE OSC 48                   ' Loader configured for 20MHz OSC on USB board
   DEFINE RESET_ORG 0x1000         ' User code start location for HID loader  
    
   INCLUDE "DT_INTS-18.bas"        ' Base Interrupt System
   INCLUDE "ReEnterPBP-18.bas"     ' Include if using PBP interrupts                                           

   LED1   VAR PORTD.0
   Loops  VAR BYTE
    
   '   Hardware configuration
   '   ====================== 
   ADCON1  =   %00001111       ' All Digital                         


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

   OSCCON = %01110000     ; Switch to internal whenever you want by just
                          ; flipping OSCCON.1 to 1.
                          ; To run at 48MHz, flip OSCCON.1 back to 0..
Main:
   FOR Loops = 1 TO 6    ' we'll run at 48MHz here
     TOGGLE PORTD.1
     Pause 500
   NEXT Loops
  
   OSCCON.1 = 1          ' we'll run at 8MHz on internal osc here 
   FOR Loops = 1 TO 6
     TOGGLE PORTD.1
     Pause 500
   NEXT Loops
   
   OSCCON.1 = 0          ' flip switch back to 48MHz
   GOTO Main

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

    END

Some day when I have time I might figure the other one out, but this took a fraction of the time to change & test.

[vamtbrider]

I think I have two problems.

One the jumper for bootloader mode is a PB that will tie portb.1 and 2 to ground when pressed. Walking through the bootloader code with the MPLAB debugger the portb inputs are not always on. Some times they are and sometimes they are not. I enabled the pull ups through the INCON2<7> but that doesn't seem to help. So I need to figure that out first.

A few times I have been able to get the DT_INTS-18 code with the blinky light to load into the PIC via the bootloader while still in debug mode in MPLABS. This has lead to the second problem.

When the interrupt comes in the code jumps to 0x008 which has a GOTO 0x808.
At 0x808 is another GOTO 0x998

running through the interrupt eventually gets to the code below:

1122   08C2    C017             MOVFF usb_sm_state, 0x90               
  1123   08C4    F090             NOP                                    
  1124   08C6    C018             MOVFF usb_sm_ctrl_state, 0x91          
  1125   08C8    F091             NOP                                    
  1126   08CA    C019             MOVFF usb_active_cfg, 0x92             
  1127   08CC    F092             NOP                                    
  1128   08CE    C01A             MOVFF usb_alt_intf, 0x93               
  1129   08D0    F093             NOP                                    
  1130   08D2    8022             BSF [0x22], 0                          
  1131   08D4    B414             BTFSC [0x14], 0x2                      
  1132   08D6    EF74             GOTO 0x8e8                             
  1133   08D8    F004             NOP                                    
  1134   08DA    C021             MOVFF 0x21, PCLATU                     
  1135   08DC    FFFB             NOP                                    
  1136   08DE    C020             MOVFF 0x20, PCLATH                     
  1137   08E0    FFFA             NOP                                    
  1138   08E2    501F             MOVF [0x1f], W                         
  1139   08E4    6AE0             CLRF BSR, ACCESS                       
  1140   08E6    6EF9             MOVWF PCL, ACCESS                      
  1141   08E8    C01E             MOVFF pSrc, PCLATU                     
  1142   08EA    FFFB             NOP                                    
  1143   08EC    C01D             MOVFF 0x1d, PCLATH                     
  1144   08EE    FFFA             NOP                                    
  1145   08F0    501C             MOVF [0x1c], W                         
  1146   08F2    6AE0             CLRF BSR, ACCESS                       
  1147   08F4    6EF9             MOVWF PCL, ACCESS                      
  1148   08F6    0004             CLRWDT                                 
  1149   08F8    A022             BTFSS [0x22], 0                        
  1150   08FA    EFB4             GOTO 0x968

the program resets after executing the instruction at 08F4 - MOVWF PCL, ACCESS. It looks like the WREG has a value of 0xDC that it is trying to stuff into PCL.

Basically the debugger stops stepping at that line, I click on the next line below it and select run to cursor the code restarts at 0x00. The bootloader checks the jumper, which is not there and then runs the app.

So basically it looks like the code keeps running to the first interrupt and then resetting the PIC.


I have attached a capture of the PIC Program Memory for what its worth.


I also loaded just the DT_INTS blinky light program onto the PIC without the bootloader. Using the MPLABS debugger i am able to see that when the code gets to the MOVWF PCL, ACCESS instruction it moves 0x34 from WREG into the PCL and the program jumps to 0x0234. The code at 0x0234 looks like the TOGGLELED1: code to actually toggle port b.0.
The code runs great without the bootloader.

Comparing the two pieces of code it looks like the bootloader version should be branching to 0x9DC...but instead I think its running off the stack and resetting the PIC.

I am now going to try and reload the DT_INTS with the bootloader and see if I can capture the PCL, PCLATH and PCLATU registers when the code attempts to move 0xDC into PCL. Hopefully I can see where it is really trying to go.

Its kind of late here in VA so I may have to tackle this tomorrow night.

Thanks for all the ideas so far.
Tom

[vamtbrider]

Ok, it looks like the code is trying to goto 0xa34 in the attached file.
It gets to 0x091C - MOVWF PCL, ACCESS and resets the PIC.

Here are the values for PC:

  Update      Address    Symbol Name      Value                      Binary     Char 

                 FE8     WREG                   0x34                  00110100    '4'
                 FF9     PCL                    0x1C                  00011100    '.'
                 FF9     PCLAT              0x0A341C 00001010 00110100 00011100  '.4.'
                 FFA     PCLATH                 0x34                  00110100    '4'
                 FFB     PCLATU                 0x0A                  00001010    '.'

The code should be going to 0x0A34 but instead resets...It never actually moves the 0x34 from Wreg into the PCL.

Any thoughts?

Thanks
Tom

[ScaleRobotics]

Thanks for the help Darrel.

I will look into it further. I had initialized stepcount to 32, then later to 8. Seems to get stuck after about two flashes of the led's.

Walter

[Darrel Taylor]

Maybe you need to set PCLATH before changing PCL?

[Bruce]

Walter,

Try this. It gives you a lot smaller table by packing two bytes into each word space. If you stick with the RETLW approach just uncomment the addwf WREG.

ASM
SineTable   
  movlw UPPER Table1
  movwf TBLPTRU
  movlw HIGH Table1
  movwf TBLPTRH
  movlw LOW Table1
  movwf TBLPTRL
  movf _STEPCOUNT,W
  ;addwf WREG     ; uncomment only if using RETLW tables VS db
  addwf TBLPTRL
  TBLRD*
  movf  TABLAT, W
  return
 
Table1
  db 0,128,148,167,185,200,213,222,228,230,228,222,213,200,185,167
  db 148,128,180,108,89,71,56,43,34,28,26,28,34,43,56,71,89,108
ENDASM

[circuitpro]

I've been trying to use DT_INTS-14 with a 16F877A. I'm getting errors when trying to compile. Code is as follows:

DEFINE    OSC 4

'Define LCD registers and bits
Define  LCD_DREG        PORTD
Define  LCD_DBIT        4
Define  LCD_RSREG       PORTE
Define  LCD_RSBIT       0
Define  LCD_EREG        PORTE
Define  LCD_EBIT        1

'OPTION_REG.6 = 0 
OPTION_REG.7=0                               'ENABLE PORTB PULLUPS
ADCON1 = 7                                   
Low PORTE.2                                  
Pause 100                                    

'INCLUDE FILES FOR DT INTERRUPTS  
INCLUDE "DT_INTS-14.bas"
INCLUDE "ReEnterPBP.bas"

X         VAR  BYTE
Y         VAR  BYTE
Z         VAR  BYTE
COUNTER   VAR  BYTE
TAG       VAR  BYTE[26]

INIT:
'INITIALIZE INTERRUPTS
ASM
INT_LIST  macro   ;IntSource,Label,Type,ResetFlag?
        INT_Handler  RBC_INT,  _BChange, PBP, yes                  
    endm
    INT_CREATE
ENDASM

@ INT_ENABLE RBC_INT

START:
COUNTER=0

MAIN:
IF COUNTER=>26 THEN
     LCDOUT $FE,1,"COUNTER: ",DEC COUNTER
     LCDOUT $FE,$C0,STR TAG\15
     COUNTER=0
ENDIF
GOTO MAIN

BChange:
COUNTER=COUNTER+1
IF PORTB.0=0 THEN
     TAG[COUNTER]=0
ENDIF
IF PORTB.1=0 THEN
     TAG[COUNTER]=1
ENDIF
@ INT_RETURN

The errors I'm getting are:
Error [113] c:(path)pbppic14.lib 1181: Symbol not previously defined (wsave)
Error [101] c:(path)code\lab-x1.asm 194: Error: (wsave variable not found,)
Error [101] c:(path)code\lab-x1.asm 258: Error: (" Add:" wsave VAR BYTE $70 SYSTEM)
Error [101] c:(path)code\lab-x1.asm 315: Error: (Chip has RAM in BANK1, but wsave1 was not found.)
etc
etc

Can somebody tell me what's wrong?

Thanks

[ScaleRobotics]

Yes, it is asking you to change the include file here:

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 out wsave1-3

' --- IF any of these three lines cause an error ?? ---------------------------- 
'       Comment them out to fix the problem ----
' -- It depends on which Chip you are using, as to which variables are needed --
wsave1  VAR BYTE    $A0     SYSTEM      ' location for W if in bank1
wsave2  VAR BYTE    $120    SYSTEM      ' location for W if in bank2
wsave3  VAR BYTE    $1A0    SYSTEM      ' location for W if in bank3

It needs to be adjusted for a few different chips. Comment out the wsave at $20, and uncomment the wsave at $70, and try commenting out the wsave1-3.

[circuitpro]

scalerobotics - Thanks very much.