Serial port write freezes the VM

> Hi,
>
> I'm developing a mod for Scratch that will allow controlling an educational
> robot via Bluetooth. I'm using SerialPort2 class that is included in Scratch
> plugin and allows opening ports by name. Everything works fine BUT, when I
> send commands in a loop, and the connection is lost (i.e. the robot was
> powered off), the VM freezes. I tried forking the port nextPutAll like that:
>
> timer := Delay forMilliseconds: 1000.
> port := SerialPort2  new.
> port openPortNamed:'COM14' baud:57600.
> process := [port nextPutAll:'test'. Transcript show:'port'.] forkAt: 1.
> [timer wait. Transcript show:'delay'. process terminate.] forkAt: 7.
>
> but with no result. Is there any way to write to a serial port with timeout?

>
> mactro
>
>
>
> --
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> On Mon, 9 Sep 2013, mactro wrote:
>
>> Hi,
>>
>> I'm developing a mod for Scratch that will allow controlling an
>> educational
>> robot via Bluetooth. I'm using SerialPort2 class that is included in
>> Scratch
>> plugin and allows opening ports by name. Everything works fine BUT, when I
>> send commands in a loop, and the connection is lost (i.e. the robot was
>> powered off), the VM freezes. I tried forking the port nextPutAll like
>> that:
>>
>> timer := Delay forMilliseconds: 1000.
>> port := SerialPort2  new.
>> port openPortNamed:'COM14' baud:57600.
>> process := [port nextPutAll:'test'. Transcript show:'port'.] forkAt: 1.
>> [timer wait. Transcript show:'delay'. process terminate.] forkAt: 7.
>>
>> but with no result. Is there any way to write to a serial port with
>> timeout?
>
>
> I can't help you with the SerialPort issue, but the process priorities 1 and
> 7 are definitely bad. Since the idle process uses priority 10, your
> processes will never run. Try using something between 11 and 39, or use the
> named priorities:
> Processor userBackgroundPriority
> Processor systemBackgroundPriority
>
>
> Levente
>
>
>>
>> mactro
>>
>>
>>
>> --
>> View this message in context:
>> http://forum.world.st/Serial-port-write-freezes-the-VM-tp4707333.html
>> Sent from the Squeak - Beginners mailing list archive at Nabble.com.
>> _______________________________________________
>> Beginners mailing list
>> [hidden email]
>> http://lists.squeakfoundation.org/mailman/listinfo/beginners
>>
> _______________________________________________
> Beginners mailing list
> [hidden email]
> http://lists.squeakfoundation.org/mailman/listinfo/beginners