Re: [ECOS] How to use CAN in poll mode?

["wang cui" <iucgnaw at msn dot com>]

I did researched the mechanism of network drivers and CAN stack.:)

The ethernet driver get polled through the "void (*poll)(struct eth_drv_sc 
*sc);" call back registered in its "eth_hwr_funs". Then Redboot can poll 
ethernet driver through a hw-independent style.

But there is no such poll callback registed in "can_lowlevel_funs". Which 
means when read a CAN device, it assumes the messages have been put into 
the buffer(during interrupt or outside poll). Anyway, there is a "bool 
(*getevent)(can_channel *priv, cyg_can_event *pevent, void *pdata);"

So I have to do a CYG_IO_SET_CONFIG_CAN_INPUT_DRAIN(added by myself) before 
every read.

> You should look at the CAN stack and see how to make it "think" you've
> had an interrupt by calling some poll() entry point.  That's how the
> network drivers work - the same drivers work in either RedBoot or full
> eCos with virtually no change.
>
> --
> ------------------------------------------------------------
> Gary Thomas                 |  Consulting for the
> MLB Associates              |    Embedded world
> ------------------------------------------------------------

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