(Programmers/Coders) NEED HELP WITH CODE.. asap!

[[N]auTiCa]

Problem solved - Thank you!

[console]

Ok.. I have two problems I am trying to code this in asm (assembly - motorola), it is in asm and my instructor is a dipshit and I don't know what to do. So can anyone help me out, you will be rewarded. Question 2 is much longer.. I need this by tomm morning.

 Here is a reference to sample code and the language - http://www.owlnet.rice.edu/~elec201/Book/6811_asm.html#SECTION001830000000000000000

Ahh, fun with 8-bit microcontrollers.

Well I'm happy to help answer questions, but I don't have time to do your homework. 

It's due tomorrow morning?  When was it assigned?

That reference guide was a nice overview, but very incomplete.  Is the rest of the manual available, documenting each instruction?  That overview doesn't show the add/subtract instructions, and it doesn't show the signed-mode branches, for ex.

Google helped find the processor reference manual:
http://www.freescale.com/files/microcontrollers/doc/ref_manual/M68HC11RM.pdf

The full instruction set is listed in Appendix A.

For problem 1, you'll want the BVS and BCS branch instructions, most likely, to handle detection of carry-overflow and complement-overflow, as is required in the problem statement.

I only skimmed problem 2, but sounds like it wants a basic bubble sort (O(n^2)).

What part are you stuck on?

Regards,

[[N]auTiCa]

Thanks console

What part?.. haha all of it, it was assigned two days ago and is due tomorrow as our final assignment for the class. The problem is my instructor does not go over anything, he is completely useless. I have been trying to figure this out all day and another friend of mine from class we are stuck and have emailed our teacher and he has not replied. I have to do the PDL and flow chart, which is no big deal.. it's the code thats getting to me. Like how do I use BVS and BCS to tell the compiler how to execute what I want it to.. I'm so lost...

Unfortunately I will be up all night trying to figure this out and I don't think I will get very far. These problems are only like 10 lines of code probably and I dunno what to do.

I'm not a programmer, although I am in engineering but will use my degree for networking basically.. so I am lost and need help 

it's also a big part of my grade which really sucks at this point considering tomorrow is the last day of class.

[[N]auTiCa]

OK this is what i have so far...

Problem 1:

              ORG $2600              /label & load table1
TABLE1  FCB "i dont know what values to put here"

              ORG $2610              /label & load table2
TABLE2  FCB "i dont know what values to put here"


              ORG $2400              /start the program
              LDX TABLE1             /initialize the index

LOOP     LDAA 00,X                /load A

...........
now I need to add the adding and I'm stuck.

[console]

it's the code thats getting to me. Like how do I use BVS and BCS to tell the compiler how to execute what I want it to..

Unlike some of motorola's other chips, such as the 680x0 series, which had lots of general-purpose registers, this 68HC11 has only a few registers, and they're fairly special-purpose.  Meaning, certain instructions only work with certain registers.

For instance, ABA, ABX, and ABY require the addend to be stored in register B.  There appears to be no way to add A to B, only B to A (for instance.)

Programming chips like this is largely about determining which kind of operations you can perform on which registers, and how to move data from register to register, and how to move data from register to memory, and memory to register.

You can move data from register A to B with TAB.  And from B to A with TBA.

You can increment and decrement A and B with INCA, INCB, and DECA, DECB.  You can also inc/dec the index registers X and Y, with INX, INY, and DEX, DEY.

One key process you're going to need to figure out how to do is looping.

Here's a simple example of looping 12 times, counting down in the A register.

                  LDAA       #12                             load immediate 12 into A
LOOPTOP    EQU        *                                  create label we can branch to to repeat our loop
                  DECA                                          subtract 1 from A, setting condition codes
                  BNE         LOOPTOP                     if condition codes say we haven't reached zero yet, go back to top


Regards,

quadz

[console]

              ORG $2600              /label & load table1
TABLE1  FCB "i dont know what values to put here"

              ORG $2610              /label & load table2
TABLE2  FCB "i dont know what values to put here"

Well, you're going to need to put 12 values in each table, that will be added together by your program and the result placed in a third table.

It looks like you get to make up the values yourself, except for the specific pairs required by the problem.

For instance, one of the required pairs is (-128, -4) and another is (126, 10), so your tables would include data fo r those pairs, like:

              ORG    $2600
TABLE1   EQU    *
              FCB    -128
              FCB    126

              ORG    $2610
TABLE2   EQU    *
              FCB     -4
              FCB     10


Regards,

quadz

[[N]auTiCa]

Thanks for the help, I appreciate it.. didn't think someone would spend the time to help me, but quakers have a special bond.. heh

OK.. understanding it much better now.. I was just about to post asking what I was to store in FCB, but a warning popped up saying a new reply was posted - thanks you read my mind.

Can't I just use this

FCB $-128,$126,$7,$8,$9.. and so on?

instead of having to make a new FCB line for each number? or is a new line required?

btw it's after 3am here east coast and I'm still stuck on #1...   

[console]

Can't I just use this

FCB $-128,$126,$7,$8,$9.. and so on?

instead of having to make a new FCB line for each number? or is a new line required?

Yeah, it looks like you can. 

[[N]auTiCa]

OK here is what i have so far... it should somewhat be complete however where do you put where to subract.. I don't even know if this is right lol
i also came across this site - http://www.seas.upenn.edu/ese/rca/hardware/6811/6811info.html

                     ORG $25FF
COUNT          FCB 12

TABLE1         FCB $-1,$+1,$-1,$-128...

                     ORG $2610
TABLE2          FCB $-1,$+1,$+1,$-4...


                     ORG $2400
                     LDX TABLE1

LOOP             LDAA 00,X

                      ADDA $10,X

                      BCC CHECKFLOW
                      LDAA #00

CHECKFLOW  STAA $30,X

                      DEC COUNT
                      BNE LOOP

                      SWI
                      END

[console]

Sorry Nautica, I went to take a short nap, and . . . . 

[[N]auTiCa]

Well my instructor finally emailed me back, he extended the deadline to 4pm est.. so I have a couple more hours to work on it....

thanks for your help console, but I still need to get #2 done lol 

[console]

If you want to paste your solution to problem 1, I can check it over . . .

[[N]auTiCa]

OK here is what I did for #1...

If it's wrong I don't have much time to go back and fix it.. I'm down to an hour  then I gotta run up to school and turn this in and I've only got the pdl and flowchart done for #2, having trouble with code... console can you look over #2 for me and help me in any way possible please, it's worth 75pts I can't let this one assignment lower my grade from a B to a C for the class.. I'm running out of time, I'm begging lol   

                     ORG $25FF
COUNT          FCB 12

TABLE1         FCB $-1,$+1,$-1,$-128...

                     ORG $2610
TABLE2          FCB $-1,$+1,$+1,$-4...


                     ORG $2400
                     LDX TABLE1

LOOP             LDAA 00,X

                      ADDA $10,X

                      BCC CHECKFLOW
                      BCS
                      LDAA #00
                      BVS

CHECKFLOW  STAA $30,X

                      INX
                      DEC COUNT
                      BNE LOOP

                      SWI
                      END

[console]

OK, well, it's not quite correct...

TABLE1         FCB $-1,$+1,$-1,$-128...

dollar sign usually means HEX... but you want decimal values, so I'd leave off the dollar sign.
Also, i wouldn't put a "...", just make up the rest of the values so you have 12 like the problem asks for.

Personally, since it asks for a "TABLE3" i would go ahead and put that in explicitly.  (Even though i see you are doing STAA $30,X so you are already doing the right thing.)

    ORG $2630
    TABLE3 EQU *

You're using BCS and BVS, but you're not actually branching anywhere.  You've got to take those branches somewhere to handle clamping the values to 127 or -128 as the problem requires.

I would get rid of the BCC CHECKFLOW... basically...

LOOP             LDAA 00,X
                     ADDA $10,X

                      BCS OVERFLOW
                      BVS UNDERFLOW

STORERESULT  STAA $30,X
                      INX
                      DEC COUNT
                      BNE LOOP
                      BRA FINISH

OVERFLOW     LDAA #127
                      BRA STORERESULT
UNDERFLOW   LDAA #-128
                      BRA STORERESULT

FINISH            SWI                      * are you really supposed to do a software interrupt to end your program?
                      END

[[N]auTiCa]

Ok I see where I went wrong.. thank you so much for the help.

Any chance of getting something for #2 for me please?

I've got a half hour left and I'm stressing on this whole stack, push, and pull.. it's a whole other concept from #1.

If you can help me with that within the next half hour I wouldn't know how to repay you.. seriously your a life saver, thank you.