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azugr@outlook.com

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Joined: Thu. Jun 10, 2021

Posts: 13 View posts

Posted by azugr@outlook.com: Thu. Jun 10, 2021 - 11:07 PM

Hi! I am lost! I really tried but my code doesn't work properly, I tried to debug, but keeps an infinite loop, and to complicated more this i need send a bit to port b.

If port D pin is 1, a "walking bit" to the left is sent to port B.

Any help will be appreciated.

.NOLIST
.INCLUDE "8515def.inc"
.LIST

rjmp begin

begin:

    ser r16        ; r16 = 0xFF
    out DDRD,r16
    clr r16        ; r16 = 0x00
    out DDRB,r16

    sbi PORTD,0
    ldi r30,3
   retraso1:
       dec r30
       breq sigue1
       rjmp retraso1
   sigue1:
    cbi PORTD,0
    ldi r30,3
   retraso2:
       dec r30
       breq sigue2
       rjmp retraso2
   sigue2:
    brne loop

loop:
    sbi PORTB,6
    ldi r30,3
   retraso3:
       dec r30
       breq sigue3
       rjmp retraso3
   sigue3:
    cbi PORTB,7
    ldi r30,3
   retraso4:
       dec r30
       breq sigue4
       rjmp retraso4
   sigue4:
    sbi PORTB,6
    ldi r30,3
   retraso5:
       dec r30
       breq sigue5
       rjmp retraso5
   sigue5:
    cbi PORTB,6
    ldi r30,3
   retraso6:
       dec r30
       breq sigue6
    rjmp retraso6
   sigue6:

    sbi PORTB,5
    ldi r30,3
   retraso7:
       dec r30
       breq sigue7
    rjmp retraso7
   sigue7:
    cbi PORTB,5
    ldi r30,3
   retraso8:
       dec r30
       breq sigue8
    rjmp retraso8
   sigue8:
    sbi PORTB,4
    ldi r30,3
   retraso9:
       dec r30
       breq sigue9
       rjmp retraso9
   sigue9:
    cbi PORTD,5
    ldi r30,3
   retraso10:
       dec r30
       breq sigue10
       rjmp retraso10
   sigue10:
    sbi PORTB,3
    ldi r30,3
   retraso11:
       dec r30
       breq sigue11
       rjmp retraso11
   sigue11:
    cbi PORTB,3
    ldi r30,3
   retraso12:
       dec r30
       breq sigue12
       rjmp retraso12
   sigue12:
    sbi PORTB,2
    ldi r30,3
   retraso13:
       dec r30
       breq sigue13
       rjmp retraso13
   sigue13:
    cbi PORTB,2
    ldi r30,3
   retraso14:
       dec r30
       breq sigue14
       rjmp retraso14
   sigue14:
    sbi PORTB,1
    ldi r30,3
   retraso15:
       dec r30
       breq sigue15
       rjmp retraso15
   sigue15:
    cbi PORTB,0
    ldi r30,3
   retraso16:
       dec r30
       breq sigue16
       rjmp retraso16
   sigue16:
    sbi PORTB,0
    ldi r30,3
   retraso17:
       dec r30
       breq sigue17
       rjmp retraso17
   sigue17:
    cbi PORTB,0
    ldi r30,3
   retraso18:
       dec r30
       breq sigue18
       rjmp retraso18

   sigue18:
    in r16,PIND
   andi r16,0b00000001

breq round_loop_longjmp
round_loop_longjmp:

rjmp loop

Azul Garcia

Tags:

AVR Microcontrollers, megaAVR and tinyAVR

Last Edited: Thu. Jun 10, 2021 - 11:26 PM

azugr@outlook.com

Level: New Member

Joined: Thu. Jun 10, 2021

Posts: 13 View posts

Posted by azugr@outlook.com: Thu. Jun 10, 2021 - 11:13 PM

This is the assignment

Read the status of a switch connected to one of the D port pins. If the pin is at 0, a "walking bit" to the right is sent to port B, that is, first activate for a certain time only pin 7 of the port, then deactivate pin 7 and activate by a time only pin 6, after pin 6 turns off and pin 5 turns on for a while, and so on until pin 0 turns on. After pin 0 turns on, the cycle repeats starting from pin 7 again. If port D pin is 1, a "walking bit" to the left is sent to port B.

Azul Garcia

avrcandies

Level: Raving Lunatic

Joined: Wed. Jun 30, 2004

Posts: 7146 View posts

Location: Cincinnati Oh

Posted by avrcandies: Fri. Jun 11, 2021 - 12:19 AM

Your code is way way way way way tooo long, should be no more than maybe 30 lines


ser XL
out DDRB, XL ;all outputs
out PORTB, XL   ; turn on pullups
clr XL
out DDRD, XL  ;all input

ldi ZL, 1

loopy:     sbis PIND, 0  ;check PDO
	   rjmp go_right
           lsl ZL
           brne show_it
	   ldi ZL, 1
	   rjmp show_it

go_right:  lsr ZL
	   brne show_it
	   ldi ZL, 128
show_it:   out PORTB, ZL

	   ser XH
	   ser XL
waitup:	   dec XL
           nop
	   nop
           nop
           nop
           brne waitup
           dec XH
           brne waitup
           rjmp loopy

When in the dark remember-the future looks brighter than ever. I look forward to being able to predict the future!

Last Edited: Fri. Jun 11, 2021 - 02:21 PM

balisong42

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Joined: Fri. Mar 20, 2009

Posts: 311 View posts

Location: Seattle, WA, USA

Posted by balisong42: Fri. Jun 11, 2021 - 12:47 AM

Double check the initialize of the DDR registers. Which port should be input and which port should be output?

avrcandies

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Joined: Wed. Jun 30, 2004

Posts: 7146 View posts

Location: Cincinnati Oh

Posted by avrcandies: Fri. Jun 11, 2021 - 02:58 AM

Double check the initialize of the DDR registers. Which port should be input and which port should be output?

Thanks, updated,--was setting DDRB twice, needed to set both DDRB & DDRD

When in the dark remember-the future looks brighter than ever. I look forward to being able to predict the future!

grohote

Level: Resident

Joined: Mon. Nov 23, 2009

Posts: 502 View posts

Posted by grohote: Fri. Jun 11, 2021 - 05:52 AM

This is the typical example why the subroutines MUST be used.

Do replace all instances of the code:

    ldi r30,3
    retrasoNN:
    dec r30
    breq sigueNN
    rjmp retrasoNN
    sigueNN:

with the code:

    rcall sDelay3
...
sDelay3:
    ldi r30,3
    retraso:
    dec r30
    breq sigue
    rjmp retraso
    sigue:
    ret

For the code insertion you have <> in the tool-list. There are 4-5 other problems with the code, we may discuss.

/The code must not be the pain in the..., and when it is readable, it is also enjoying./

Last Edited: Fri. Jun 11, 2021 - 05:53 AM

clawson

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Joined: Mon. Jul 18, 2005

Posts: 102557 View posts

Location: (using avr-gcc in) Finchingfield, Essex, England

Posted by clawson: Fri. Jun 11, 2021 - 08:15 AM

Seems to me the "walking 1 bit" is a test to see if you know about shifts and rotates. What I don't think they are looking for is a load of:

    SBI 7
    RCALL delay
    SBI 6
    CBI 7
    RCALL delay
    SBI 5
    CBI 6
    RCALL delay
    ...

What I think he's looking for is a simple loop:

   LDI count, 8
   SBI PORTB, 7
loop:
   IN R16, PORTB
   LSR R16
   OUT PORTB, R16
   RCALL delay
   DEC count
   BRNE loop

where the very key thing in that is knowing that the instruction that will make 0x80 follow the sequence 0x80, 0x40, 0x20, 0x10... is the LSR in the middle.

Last Edited: Fri. Jun 11, 2021 - 08:23 AM

avrcandies

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Joined: Wed. Jun 30, 2004

Posts: 7146 View posts

Location: Cincinnati Oh

Posted by avrcandies: Fri. Jun 11, 2021 - 01:23 PM

This is the typical example why the subroutines MUST be used.

There is no need at all for a subroutine (saying it must be used gives a wrong impression)...the delay happens at all times (though calling it as a sub can allow it to be used in other parts of the program)...but then this chip, would prob also need the stack pointer set.. so it is more efficient to use as an inline delay.

Unfortunately the AVR doesn't have a rotate without carry, so it is just as easy to reinit when the LSL/LSR shifted value runs dry (which has the advantage that if some rouge value got in, it wouldn't just rotate around forever).

When in the dark remember-the future looks brighter than ever. I look forward to being able to predict the future!

grohote

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Joined: Mon. Nov 23, 2009

Posts: 502 View posts

Posted by grohote: Fri. Jun 11, 2021 - 02:05 PM (Reply to #8)

Interesting observation.

Once I started my first design it was really necessary ("Just do subroutines"). Of course that the subs are not strictly necessary in the C-programming, and I wonder is it worth time to strip the code of them also in ASM.

The worse what can happen to the ASM code is the spaghetti-coding. As long as the code diagram can be kept on A4 size, anything legal is allowed to do with the ASM code.

The skill you produced the #3 code is admirable, how any beginner may think that way, me included.

azugr@outlook.com

Level: New Member

Joined: Thu. Jun 10, 2021

Posts: 13 View posts

#10

Posted by azugr@outlook.com: Fri. Jun 11, 2021 - 02:15 PM (Reply to #3)

Thanks so much, for your commentary, i didn't have any idea how to make it short.

Azul Garcia

azugr@outlook.com

Level: New Member

Joined: Thu. Jun 10, 2021

Posts: 13 View posts

#11

Posted by azugr@outlook.com: Fri. Jun 11, 2021 - 02:18 PM (Reply to #4)

Thanks for your help, the input port is B, the outport is D

Azul Garcia

azugr@outlook.com

Level: New Member

Joined: Thu. Jun 10, 2021

Posts: 13 View posts

#12

Posted by azugr@outlook.com: Fri. Jun 11, 2021 - 02:19 PM (Reply to #4)

Thanks for your help, I am studing how to code but I am having a hard time to simplify it, the good news I am keep trying.

Azul Garcia

Last Edited: Fri. Jun 11, 2021 - 03:12 PM

azugr@outlook.com

Level: New Member

Joined: Thu. Jun 10, 2021

Posts: 13 View posts

#13

Posted by azugr@outlook.com: Fri. Jun 11, 2021 - 03:07 PM

Wow! I really appreciate your help! I will keep trying to learn code.

Azul Garcia

grohote

Level: Resident

Joined: Mon. Nov 23, 2009

Posts: 502 View posts

#14

Posted by grohote: Fri. Jun 11, 2021 - 04:39 PM

azugr@outlook.com wrote:

I will keep trying to learn code.

Just keep trying. The best code learn is by coding and testing.

Milan

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