program

Archiver

hi :-)

i'm trying to write a program for the BS2 where i connect LED's to the
pins to demonstrate the algorithm i programmed in. When i built this i
will have actual external circuits connected to the pins but for now
i just want to have the controller run through different scenarios

any suggestion would be great.....

'=== constanst and pin
motion con pin 0
noise con pin 1
glass con pin 2
door con pin 3
buzz con pin 7
light con pin 8
light1 con pin 9


motion var bit
noise var bit
glass var bit
door var bit

motion = 0
noise = 1
glass = 1
door = 0

GOSUB check

motion = 1
noise = 0
glass = 1
door = 1

GOSUB check

motion = 1
noise = 1
glass = 1
door = 1

GOSUB check

end

check:
IF motion = 0 AMD noise = 1 AND glass = 1 AND door = 1
THEN LED
IF noise = 0 AND motion = 1 AND glass = 1 AND door = 1
THEN message
IF glass = 0 AND motion =1 AND noise = 1 AND door = 1
THEN message
IF door =0 AND noise = 1 AND glass = 1 AND motion = 1
THEN message

IF motion = 0 AND noise = 0 THEN Alarm
IF motion = 0 AND glass = 0 THEN Alarm
IF motion = 0 and door = 0 THEN Alarm
IF noise = 0 AND glass = 0 THEN Alarm
IF noise = 0 AND door = 0 THEN Alarm
IF glass = 0 AND door = 0 THEN Alarm

RETURN

LED:
low light
pause 250
high light
RETURN

Message:
FOR counter 0 to 3
GOSUB blink
NEXT

blink:
low light1
pause 50
high light1
pause 50
RETURN

Alarm:
low buzz
pause 50
high buzz
RETURN


does this look correct? i'm confused about the declaring the direction
of the pins and the input and output pins?? i have the scott edwards book
and the manual from the website but it's not clear to me

saying low light -- does that automatically make it a output?

- LaQuida

Archiver

I am trying to develop a program that I can insert into a line of Pbasic
code that will look at an input and will count the number of transitions
it makes from 0-1 and 1-0. I don't want it to slow the cpu down and I
only want it add to the count when the input changes. Any one had
experience in this area?


Kind regards,


Leroy

Archiver

Leroy,
In just 1 line of code you can 'read' the staus of stamp inputs to
determine if anything has changed. If an input has changed you can
then go to a lookup table that will perform the appropriate function,
in your case start counting. here is a sample of the code. The inl
instruction looks at the low byte of ins, or pins 0 through 7 (ins
looks at all 16). Mine were all active low inputs (normally at 5
volts but pulled to 0 when activated). 255 means all were high and
none were activated. If one of the inputs was activated (low) inl
would be < than 255 and would continue on after the if then. This
detection loop runs in ~500 us and cold be run periodically while
doing other stuff.


cell_detect:
if inl = 255 then cell_detect 'inl Looks at pins 0-7. 255 = all high.
io_status = inl ' Write the input status to a variable.

x = 0
for x = 0 to 255
lookdown io_status,[noparse][[/noparse]254,253,251,247,239,223,191,127],look_index
branch
look_index,[noparse][[/noparse]cell_43,cell_44,cell_45,cell_46,cell_47,cell_48,cell_49,ce
ll_50]
next
goto cell_detect



> I am trying to develop a program that I can insert into a line of
Pbasic
> code that will look at an input and will count the number of
transitions
> it makes from 0-1 and 1-0. I don't want it to slow the cpu down
and I
> only want it add to the count when the input changes. Any one had
> experience in this area?
>
>
> Kind regards,
>
>
> Leroy

Archiver

My input signal is going to be turning on for 1/2 second and then off
for one half second. I want a variable to keep track of how many times
this occurs, without slowing down the processor. is suedo code:

start

Look at input and check if on or off

if on goto to "on"
if off goto "off"

goto start


on:
if a transition just occurred from off to on add one to count
return


off:

do something???

Thanks for your help, the group is just great..

Leroy

Archiver

Hi Leroy,

Lets define ON and OFF

OFF con 0
ON con 1

Oldin var bit
Newin var bit
Count var word

Assume input 1 is our input

Newin=in1

Loop:
Oldin=newin
Newin=in1
If newin ^ oldin & newin = 0 then continue
Count=count+1 'only if transition from 0 to 1
Continue:
Do something
Goto loop

Greetings peter

Archiver

Hi Leroy,

One extra remark: your 'do something' code MUST take less than 0.5 secs or
You will miss transitions.

Freetings peter

Archiver

If I understand correctly, you want the code to take the same amount of time
to execute whether a transition is detected or not?

---

Original Message

---

> One extra remark: your 'do something' code MUST take less than 0.5 secs or
> You will miss transitions.

Archiver

Hi Rodent and Leroy,

The code executed when the input is ON or OFF may be different but must be
less then the time
Leroy specified: 0.5secs ON and 0.5secs OFF.
If the 'do something' would take 0.6secs, a positive AND negative transition
can occur while executing
the code for the OFF state resulting in a missed 0 -> 1 transition. Things
would even get worse if the input
was ON for 0.1secs and OFF for 0.9secs, then the execution time should be
less than 0.1secs.

Hope this clearifies the difficulty counting pulses while performing other
tasks.

Greetings peter

Archiver

Just read the port and add it to a counter. If its zero, the counter is not
incremented -- if its one, well...

A hex or binary 1 will add to a decimal counter with no problems.

---

Original Message

---

> The code executed when the input is ON or OFF may be different but must be
> less then the time
> Leroy specified: 0.5secs ON and 0.5secs OFF.
> If the 'do something' would take 0.6secs, a positive AND negative
transition
> can occur while executing
> the code for the OFF state resulting in a missed 0 -> 1 transition. Things
> would even get worse if the input
> was ON for 0.1secs and OFF for 0.9secs, then the execution time should be
> less than 0.1secs.
>
> Hope this clearifies the difficulty counting pulses while performing other
> tasks.

Archiver

Hi Rodent,

>Just read the port and add it to a counter. If its zero, the counter is not
>incremented -- if its one, well...

>A hex or binary 1 will add to a decimal counter with no problems.


As Leroy wants to count transitions, the above does not work.
If I read the port the second time and it is still ON then my
Count will not reflect the number of transitions. Sorry.


Greetings peter

Archiver

Hi Rodent and Leroy,

I could add the expression after the IF to the counter.
If an entry point for code at a transition is not needed
things can be simplified to:

Lets define ON and OFF

OFF con 0
ON con 1

Oldin var bit
Newin var bit
Count var word

Assume input 1 is our input

Newin=in1

Loop:
Oldin=newin
Newin=in1
Count = newin ^ oldin & newin + count
Do something
Goto loop

The time constraint for 'do something' still holds.

Greetings peter

Archiver

To add one to the count whenever it changes state,

old var bit ' state variable
new var bit ' state variable
all var word ' counter
old=in0 ' init state variable
loop:
new=in0 ' read the input
all=new ^ old + all ' count transition if any
old=new ' update the state
' other stuff
goto loop

The code is constant time, about 1 millisecond, and it does not use
any if-then logic, only math. To count only 0-1 transitions, the
expression should be
all=new ^ old & new + all
Or to count only 1-0 transitions, use,
all=new ^ old & old + all

-- regards,
Tracy Allen
electronically monitored ecosystems
mailto:tracy@e...
http://www.emesystems.com


At 3:23 PM -0400 6/24/01, Leroy Hall, Senior wrote:
>>>I am trying to develop a program that I can insert into a line of Pbasic
>>>code that will look at an input and will count the number of transitions
>>>it makes from 0-1 and 1-0. I don't want it to slow the cpu down and I
>>>only want it add to the count when the input changes. Any one had
>>>experience in this area?
>>>
>>>
>>>Kind regards,
>>>
>>>
>>>Leroy

"Peter Verkaik" <peterverkaik@b...> wrote:
>>Hi Leroy,
>>
>>Lets define ON and OFF
>>
>>OFF con 0
>>ON con 1
>>
>>Oldin var bit
>>Newin var bit
>>Count var word
>>
>>Assume input 1 is our input
>>
>>Newin=in1
>>
>>Loop:
>>Oldin=newin
>>Newin=in1
>>If newin ^ oldin & newin = 0 then continue
>>Count=count+1 'only if transition from 0 to 1
>>Continue:
>>Do something
>>Goto loop
>>
>>Greetings peter

count is a reserved variable!!


At 10:11 AM -0500 6/25/01, Rodent wrote:
>Just read the port and add it to a counter. If its zero, the counter is not
>incremented -- if its one, well...
>
>A hex or binary 1 will add to a decimal counter with no problems.


But he wants it to add to the count only when it makes a transition!

Archiver

HI,

Could anyone help me with this code.
I want to convert it to a PIC16F84 but don't know where to start.


Ren

Archiver

For rene:

There was no code attached, but generally, converting to PIC from Stamp is
pretty simple. However, you will need a PICPro Basic compiler before you can
compile and load the program. You will also need an editor such as
"MicroCode Studio", which is a free download, and a programmer like the
WARP-13.

For a start, with PIC you always have to add

Define osc 20 (if you are using a 20mhZ resonator) at the very beginning of
your program.

serouts become serout2 and serins become serin2

If I can help you with specifics I will be happy to do so.

Sid


[noparse][[/noparse]Non-text portions of this message have been removed]

Archiver

At 16:45 05/19/02, Ren