--- In l..., "flashzr" wrote:
>
> --- In l..., "zoran.mijanovic" wrote:
> >
> > UART0 can be used for both: as programming port and to communicate with another CPU.

If your programming one of the two CPUs, then the other one must not do anything to hinder the programming process.

So put the other CPU into RESET.

If its in RESET, all the IO pins are tri-stated and can not bother the programming process.

hamilton

>
> And how do I prevent another CPU from listening and responding
> to ISP commands issued to LPC?
>
> Also, TXD from another CPU and TXD from ISP programmer will be in
> short circuit, if I don't add some complexity (a jumper, at least),
> which I'd rather not.
> > You can also use UART1. If you need not modem signals RTS, DRT, etc, just don't use them. Read carefully LPC user manual and set USART1 registers appropriately.
>
> Simple as that? Should I assign them as regular I/O pins?
>
> Using UART1 as simple UART would be best, as this guy wants:
> http://embeddedrelated.com/groups/lpc2000/show/3285.php
> just that I wish to use RXD and TXD only.
>

Start a New Thread

> On Fri, Jan 7, 2011 at 2:28 PM, flashzr wrote:

> Q: Can I disable the modem control signals in UART1
> that I don't really need?

--- In l..., David Smead wrote:

> Don't enable the modem control signals.

How do I enable/disable those?

Start a New Thread

--- In l..., "flashzr" wrote:
>
> > On Fri, Jan 7, 2011 at 2:28 PM, flashzr wrote:
>
> > Q: Can I disable the modem control signals in UART1
> > that I don't really need?
>
> --- In l..., David Smead wrote:
>
> > Don't enable the modem control signals.
>
> How do I enable/disable those?
>

From table 111 you can see how to disable hardware flow control. Software flow control only works if you write the code. Don't write it!

You are under no obligation to even set the pin modes for flow control. You can simply configure them for GPIO - table 59.

Richard

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Also, do not forget to enable the RX buffer, (you should enable the TX too),
the RX Buffer can store 16 (or 14, dont remember) bytes. It is very useful
to give the main program extra time to do its stuff if required.

2011/1/8 rtstofer

> --- In l... , "flashzr"
> wrote:
> >
> > > On Fri, Jan 7, 2011 at 2:28 PM, flashzr wrote:
> >
> > > Q: Can I disable the modem control signals in UART1
> > > that I don't really need?
> >
> > --- In l... , David Smead
> wrote:
> >
> > > Don't enable the modem control signals.
> >
> > How do I enable/disable those?
> > From table 111 you can see how to disable hardware flow control. Software
> flow control only works if you write the code. Don't write it!
>
> You are under no obligation to even set the pin modes for flow control. You
> can simply configure them for GPIO - table 59.
>
> Richard
>
>
> Start a New Thread