Multitasking ?

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cicciocb
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Re: Multitasking ?

Post by cicciocb »

Thanks for the advices, I'll try to improve in the future
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Re: Multitasking ?

Post by cicciocb »

I'm doing some testing with the DS18B20
The goal is to improve the command without breaking the existing syntax.
Initially I planned to introduce a new command but I think I found a good compromise.

This should be the final syntax

Code: [Local Link Removed for Guests]

ret$ = TEMPR$(pin, [id], [resolution])
The function continue to work as before (as documented in the help file)

Additionally, the parameter "resolution' can be provided (from 9 to 12 bits).
The resolution determine the minimal increment of temperature and also the conversion time (see table below)
image.png
if the resolution is ignored, it default to 12 as before.

The novelty is now the async mode :
Giving 0 as ID, starts the conversion on all the DS18B20 sensors connected without waiting for the answer

For example

Code: [Local Link Removed for Guests]

ret$ = TEMPR$(2, 0) ' starts an async read on the pin 2
The result will be the string "START"

Then, it will be possible to read the devices as below

Code: [Local Link Removed for Guests]

ret1$ = TEMPR$(2, 1) 'read the 1st sensor on the pin 2
ret2$ = TEMPR$(2, 2) 'read the 2nd sensor on the pin 2
In this case, if the value is not yet available (during the conversion time) the result will be "WAIT' that will be replaced by the good value at the end of the conversion.

To restart another conversion, the same command must be executed

Code: [Local Link Removed for Guests]

ret$ = TEMPR$(2, 0) ' starts an async read on the pin 2
What do think ?
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Re: Multitasking ?

Post by rmsta »

Really good proposal for time critical applications and easy to understand !
I think for many projects (also mine) the paramter "resolution" will be most beneficial.
Hopefully it will be available soon :-)
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Re: Multitasking ?

Post by MarioL »

Hi,
if i understand correctly in async mode and with the following code
no waiting time for conversion, no lost time.
(all sensors convert simultaneously, 750ms required, ESP is free)
It's very cool and suitable if many sensors are employed and hight resolution is needed

Se ho capito bene, in modalità asincrona e col seguente codice non c'e da attendere il tempo di conversione, quindi non c'e tempo perso.
(tutti i sensori convertono contemporaneamente nei 750ms e l'ESP è libero di effettuare altre operazioni)
Questo è il massimo se si impiegano molti sensori ed è richiesta la risoluzione a 12 bit.

Code: [Local Link Removed for Guests]

code:

ret$ = TEMPR$(2, 0) ' starts of async conversion  on the pin 2 for first read

gosub lbl_draw_page
onHtmlReload draw_page
'other code lines
timer0 1000, lbl_read_temp  
wait

lbl_read_temp:
 ret1$ = TEMPR$(2, 1) 'read the 1st sensor on the pin 2
 ret2$ = TEMPR$(2, 2) 'read the 2nd sensor on the pin 2
 ret1$ = TEMPR$(2, 3) 'read the 3st sensor on the pin 2
 ret2$ = TEMPR$(2, 4) 'read the 4nd sensor on the pin 2
 ret$ = TEMPR$(2, 0) ' starts an async conversion  on the pin 2 for next read
return
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Re: Multitasking ?

Post by cicciocb »

[Local Link Removed for Guests] wrote: [Local Link Removed for Guests]Mon Jan 23, 2023 9:25 pm Hi,
if i understand correctly in async mode and with the following code
no waiting time for conversion, no lost time.
(all sensors convert simultaneously, 750ms required, ESP is free)
It's very cool and suitable if many sensors are employed and hight resolution is needed

Se ho capito bene, in modalità asincrona e col seguente codice non c'e da attendere il tempo di conversione, quindi non c'e tempo perso.
(tutti i sensori convertono contemporaneamente nei 750ms e l'ESP è libero di effettuare altre operazioni)
Questo è il massimo se si impiegano molti sensori ed è richiesta la risoluzione a 12 bit.

Code: [Local Link Removed for Guests]

code:

ret$ = TEMPR$(2, 0) ' starts of async conversion  on the pin 2 for first read

gosub lbl_draw_page
onHtmlReload draw_page
'other code lines
timer0 1000, lbl_read_temp  
wait

lbl_read_temp:
 ret1$ = TEMPR$(2, 1) 'read the 1st sensor on the pin 2
 ret2$ = TEMPR$(2, 2) 'read the 2nd sensor on the pin 2
 ret1$ = TEMPR$(2, 3) 'read the 3st sensor on the pin 2
 ret2$ = TEMPR$(2, 4) 'read the 4nd sensor on the pin 2
 ret$ = TEMPR$(2, 0) ' starts an async conversion  on the pin 2 for next read
return
Yes, what you say is correct, I just need to test with several devices at the same time
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Re: Multitasking ?

Post by BeanieBots »

Looks like a good compromise between full one-wire functionality and ease of use.
Just to be clear, does TEMPR$(2,0) start the conversion on ALL DS18B20's connected to GPIO.2 and is it normal(3-wire) powered mode or parasitic(2-wire) mode?
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Re: Multitasking ?

Post by cicciocb »

[Local Link Removed for Guests] wrote: [Local Link Removed for Guests]Tue Jan 24, 2023 9:30 am Looks like a good compromise between full one-wire functionality and ease of use.
Just to be clear, does TEMPR$(2,0) start the conversion on ALL DS18B20's connected to GPIO.2 and is it normal(3-wire) powered mode or parasitic(2-wire) mode?
I need to continue the testing (I tested with only one DS12B20 so far) but the conversion should start on all the devices at the same time.
So far I tested only in normal mode but it should work also in parasitic mode
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Re: Multitasking ?

Post by cicciocb »

I can confirm that it works as expected (I tested on an ESP32-S3).
Will be in the next release
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Re: Multitasking ?

Post by BeanieBots »

Any chance we might see it for 8266 as well?
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Re: Multitasking ?

Post by cicciocb »

[Local Link Removed for Guests] wrote: [Local Link Removed for Guests]Fri Jan 27, 2023 5:30 pm Any chance we might see it for 8266 as well?
I'll try to include the changes also in the ESP8266
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