32-bit Variables and DIV32, Hourmeter 99999.9

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- 22nd June 2005, 04:15
Darrel Taylor

32-bit Variables and DIV32, Hourmeter 99999.9

Continuing the series of using DIV32

If you missed them, the first 2 threads are ...
Retrieving 32bit Multiply Result
Retrieving Div32 Remainder

Here's another macro that allows you to use a 32-bit variable as the input to DIV32.

Code:

;----[Load a 32-bit (Dword) variable into PBP registers, Prior to DIV32]-------- Asm PutMulResult?D macro Din MOVE?BB Din, R2 MOVE?BB Din + 1 , R2 + 1 MOVE?BB Din + 2, R0 MOVE?BB Din + 3, R0 + 1 RST?RP endm EndAsm

Now, before you ask ... Yes, PicBasic Pro does allow 32-bit variables, it just doesn't handle them for you.

A recent request from someone here was to have a Runtime Hourmeter that counts up to 99999.9 hours. Since it takes more than 65535 to hold the value, how can you (1) keep track of that large of a number and (2) Display the number once you have it.

Let's look at the first part, Making a 32-bit variable.

Code:

Hours VAR WORD[2] ; 32-bit (Dword) HoursH VAR Hours(1) HoursL Var Hours(0)

The above will create a 2 word Array called Hours.
HoursL points to the low Word - Hours(0)
HoursH points to the high Word - Hours(1)

Since it's only going to be counting time, all we need to do is add 1 each time. Fortunately, that makes things easy. This next routine should be called once every 6 minutes (.1 hour) preferably timed by Interrupts.

Code:

;----[Add 1 tenth of an hour to the hourmeter]---------------------------------- AddHourTenth: HoursL = HoursL + 1 IF HoursL = 0 then HoursH = HoursH + 1 if (HoursH = $F) and (HoursL = $4240) then ; Roll over at 1,000,000 HoursH = 0 ; 99999.9 + .1 HoursL = 0 endif return

And all that's left to do is display it (2)
For this it takes a little trick that was descibed in the Retrieving Div32 Remainder thread.

Let's say the value of Hours is 917,456. To get this down to usable numbers we can use DIV32.

First, load the 32-bit Hours value into PBP's registers using PutMulResult?D

Code:

@ PutMulResult?D _Hours

then DIV32 that by 1000

Code:

Result = DIV32 1000 Remainder = R2

Notice that you have to get the remainder immediately after the DIV32.

So now you have the first 917 in the Result variable and the last 456 in the Remainder variable. All the digits are there, it's just a matter of displaying them.

Code:

LCDOUT $FE, 2 ; Home Cursor IF Result > 0 then LCDOUT Dec Result, DEC2 Remainder/10,".",DEC1 Remainder//10 else LCDOUT DEC Remainder/10,".",DEC1 Remainder//10 endif

This of course will display 91745.6

Here's the whole program for the Hourmeter. Timing not included

Code:

Hours VAR WORD[2] ; 32-bit (Dword) Holds up to 99999.9 hours HoursH VAR Hours(1) HoursL Var Hours(0) Result Var Word Remainder Var Word ;----[Load a 32-bit (Dword) variable into PBP registers, Prior to DIV32]-------- Asm PutMulResult?D macro Din MOVE?BB Din, R2 MOVE?BB Din + 1 , R2 + 1 MOVE?BB Din + 2, R0 MOVE?BB Din + 3, R0 + 1 RST?RP endm EndAsm ;====[Simple loop to test the HourMeter]======================================== MainLoop: gosub AddHourTenth Gosub ShowHourMeter goto MainLoop ;============================================================ ;----[Add 1 tenth of an hour to the hourmeter]---------------------------------- AddHourTenth: HoursL = HoursL + 1 IF HoursL = 0 then HoursH = HoursH + 1 if (HoursH = $F) and (HoursL = $4240) then ; Roll over at 1,000,000 HoursH = 0 ; 99999.9 + .1 HoursL = 0 endif return ;----[Display hourmeter using LCDOUT]------------------------------------------- ShowHourMeter: @ PutMulResult?D _Hours Result = DIV32 1000 Remainder = R2 LCDOUT $FE, 2 ; Home Cursor IF Result > 0 then LCDOUT Dec Result, DEC2 Remainder/10,".",DEC1 Remainder//10 else LCDOUT DEC Remainder/10,".",DEC1 Remainder//10 endif return

Best regards,
   Darrel Taylor
- 2nd March 2006, 14:46
palmed

very large result with DIV32

Hi,

this is my first post, I'm German so please excuse, if my English is not so very well.

I often used DIV32 before and never had a problem. It works fine.

Now I have the problem, that I have to produce a reciprocal value, to be exact, I have to divide 1,25E9 by values between 6200 and 32000. Dividing by 32000 is no problem again, I'll get 1,25E9/32000=39062, but dividing by 6200 will result in 1,25E9/6200=201612, which is way beyond a word variable.
Does anybody know if there is a chance to access this result?

Any help is greatly appreciated.

Peter
- 2nd March 2006, 21:16
Darrel Taylor

Hi Peter,

Sure, you can do it.

First off, you'll need to lose one of zero's from that 1,250,000,000

If you start off with 125,000,000 it brings it down to a managable range.

125,000,000 / 32000 = 3906.2
125,000,000 / 6200 = 20161.2

Then you have most of the number from the integer portion, and the last digit is in the remainder, in the form of a Modulas. By dividing the (Modulas*10) by the original divisor, you can recover the last digit.

Code:

Temp VAR WORD Divisor VAR WORD Remainder VAR WORD ;----[Load a 32-bit constant into PBP registers, Prior to DIV32]-------- ASM PutMulResult macro Const32 MOVE?CB low Const32, R2 MOVE?CB low (Const32 >> 8), R2 + 1 MOVE?CB low (Const32 >> 16), R0 MOVE?CB low (Const32 >> 24), R0 + 1 endm ENDASM Divisor = 6200 @ PutMulResult 125000000 Temp = DIV32 Divisor Remainder = R2 * 10 Remainder = DIV32 Divisor LCDOUT "Result=",DEC Temp,DEC1 Remainder

Result = 201612

HTH,
  Darrel
- 3rd March 2006, 08:38
palmed

Hi, Darrel,

thanks a lot. After all, the answer was contained in some postings before, but sometimes you "don't see the trees in the wood" (correct saying?).

I tested it and it works great!

Peter
- 2nd August 2006, 02:04
Charles Linquis

Darrel,

You constantly amaze me. What would this forum do without you?
- 2nd August 2006, 03:34
mister_e

probably just trying to use the PBP statement stated in the manual or ... hum hum.. change to another boat... wich, after trying, i reaaaallly don't recommend :)
- 2nd August 2006, 16:55
Darrel Taylor

Thanks Charles,

And, without me... The forum would be reading a lot more SPAM from PCB houses in China. :)   Love that delete command.

But, with over 2400 posts, I'm wondering what we'd do without mister_e.
Glad he didn't like the other boat. He makes up for like 10 people.

DT
- 2nd August 2006, 17:22
mister_e

The first one to blame here is Bruce... if i'd never discover his website, i'd never buyed this addictive compiler... can't live without! Chances are that the other boat wasn't buyed from him... i would hate him now LMAO!

Well thanks to the forum ! I learn almost everything here by trying to help other with their questions. Learning by trying/debugging never killed.. kinda challenge. My avatar choice says long ;) It also give me a better english.. oh yeah far to be perfect but better than before... i guess... i hope. Where are my firsts posts?

Thanks Darrel, Bruce, Melanie and all other gurus... i wish one day i'll be as good as you are!
- 23rd November 2006, 06:48
charudatt

Just remember Godess of Wisdom and Godess of Wealth can not stay in a single house.

Thanks steve for your tip in #6 on the other boat. I was about to buy it.

Thanks once again for sharing your wisdom on this forum, which goes to all the guru's.

really appreciate help from all.

regards
- 23rd November 2006, 07:23
mister_e

My pleasure Charudatt AND you're welcome!