P2 WAITCNT

pic18f2550 · 2021-03-04 10:39

Hello,

this command does not exist in P2.

How can I recreate this on the P2?

iseries · 2021-03-04 10:51

I believe this has been replaced with WAITX.

Mike

pic18f2550 · 2021-03-04 11:10

If I read the description of "WAITX" correctly, you can stop the COG by n CLOCK pulses.

I have to start a program loop, with different length, but always at the same time.

This was no problem with WAITCNT because a value was simply added to the counter.

iseries · 2021-03-04 11:40

Please check this out.

https://forums.parallax.com/discussion/comment/1448060/#Comment_1448060

Mike

Ariba · 2021-03-04 11:48

WAITCNT is now called WAITCT1..3 in PASM and you use it together with ADDCT1..3. So you can handle 3 different time periods.
It's all described in the documentation (see chapter: Events)

In Spin2 it's just WAITCT().

Andy

Cluso99 · 2021-03-04 12:04

See the p2 tricks and traps reference thread for p2 replacement code

pic18f2550 · 2021-03-04 14:10

Thank you.

JonnyMac · 2021-03-04 21:19

As the waitct? instructions do not reload the timer, you have to use addct? first.

pub blinker(pin, count, hitix, lotix) | t

  org
                getct     t

.loop           drvh      pin
                addct1    t, hitix
                waitct1
                drvl      pin
                addct1    t, lotix
                waitct1
                djnz      count, #.loop
  end

pic18f2550 · 2021-03-04 22:22

I have already taken over.

https://forums.parallax.com/discussion/173049/p2-pasm-sin-16bit#latest

pic18f2550 · 2021-06-29 10:16

How does waitcnt behave when the time is up?

The code is processed without interruption and the associated flag is cleared?

In the example, I simply want to limit the repetition rate to a maximum value.
Falling below this value is not a problem.

CON
  _clkfreq = 20_000_000

pub blinker(pin, hitix, lotix) | t

  org
                jmp       #.go

.loop
                '' routine unbekannter länge
                '' der zeitbedarf ist unter oder über hitix
                waitct1
.go             getct     t
                addct1    t, hitix
                drvh      pin

                '' routine unbekannter länge
                '' der zeitbedarf ist unter oder über lotix
                waitct1
                getct     t
                addct1    t, lotix
                drvl      pin

                jmp      #.loop
  end

evanh · 2021-06-29 11:50

@pic18f2550 said:
How does waitcnt behave when the time is up?

The code is processed without interruption and the associated flag is cleared?

Yes.

In the example, I simply want to limit the repetition rate to a maximum value.
Falling below this value is not a problem.
                ...
                waitct1
.go             getct     t
                addct1    t, hitix
                ...
                waitct1
                getct     t
                addct1    t, lotix
                ...

Correct use of recurring GETCT. It starts a fresh timeout each time.

pic18f2550 · 2021-06-29 12:05

Since the variable t is reloaded each time overflow occurs,
the values hitix and lotix should be set to 2 less.

Then everything should fit.

evanh · 2021-06-29 18:58

@pic18f2550 said:
Since the variable t is reloaded each time overflow occurs,
the values hitix and lotix should be set to 2 less.

Then everything should fit.

I wouldn't bother unless it costs nothing. It won't be consistent upon overruns.

TonyB_ · 2021-06-30 13:09

I think JNCTx could replace WAITCTx if
(a) absolute precision is not needed
(b) waits must be interruptible.

Replace

        waitct1

with

.loop       jnct1   #.loop

Am I correct?

pic18f2550 · 2021-06-30 15:02

A background is the runtime monitoring of several program pieces.
This should already be accurate.

P2 WAITCNT

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