Mail Archives: djgpp/1998/07/31/09:50:43
Neil Townsend wrote:
> Many thanks for developping the dzcomm library. However, I am having a
> little problem with it. I have posted details to the djgpp newsgroup but
> I don't know if you read it! I am quite happy to do a little thinking
> and trying if you have any suggestions. Here's the problem:
>
Sorry for delay with replay, I just was in month's holiday and recently
come back.
> I have configured the card as follows:
>
> ch. irq i/o base addr
> 1 3 300
> 2 3 308
> 3 3 310
> 4 3 318
>
Hm, I don't think irq 3 for all four ports is good thing then using dzcomm.
> (The card works just fine under DOS using the manufacturers drivers
> which are, of course, incompatible with protected mode, and have so far
> not let let me have a look at their source code.)
>
Yes, it's approve my thoughts about singl irq , I mean what manufacturer of
your cardcan make some additional hardware circuits (just very simple
signal line) and it's
software driver knows about it but dzcomm don't.
> I thought that this might be due to the interupt handler returning 0
> (which stops interupt chaining) but the behaviour was the identical when
> I changed the return value to non zero.
Moreover, returning 0 from irq handler may lead your programm to crash.See
changes file for more details.
> What is interesting is that a small quantity of data is read from the
> first channel which is set up, presumably the data which is acquired
> before the second channel is set up. I can only conclude that the
> setting up of the second channel has somehow scuppered both channels,
> although how is not clear to me.
>
> Another intertesting effect is that If I execute term, quit and then run
> it again it hangs, the only solution beign ctrl-alt-delete which forces
> a reboot and is not trapped by DJGPP.
Yes, I know such behaviour of dzcomm, I learned it then setup two comm card
at single irq.Probably, if you can send me more informaion about your card
(manufacturer, model, etc.)
I try to solve this problem.
> ps. sorry if the formatter is horrible, I'm not very au-fait with this
> editor.
Never mind.
PS. you may take a look at ser_port.txt from dzcomm.zip for information
about irq sharing.
--
____ ____
| \ / Dim Zegebart
____/____
Moscow Russia
WWW - http://www.geocities.com/siliconvalley/pines/7817
DZcomm - comm library for Allegro
Palantir - multitasking kernel for Allegro (based on PDMLWP)
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