Michael,
What kind if ESD protection do you have? The NXP LPCxxxx io pads will
latchup at 6~7Volts and a power down is needed to reset the SCRs.
Hope this helps,
Michael Freeman
Principal Design Engineer
Update Systems, Inc.
-----Original Message-----
From: l... [mailto:l...]On Behalf Of
mlcchemtrac
Sent: Friday, October 17, 2008 11:01 AM
To: l...
Subject: [lpc2000] LPC2148 UART0 failure to receive
We need to be able to disconnect and reconnect our serial
communications without causing a system upset.
Here is the kicker... The UART operates correctly, RS232 9600 baud.
However, when the RS232 cable is disconnected then at some later time
reconnected the UART will not receive any data. I have scoped the
signal through the MAX3232 and it looks as I expect.
In my code the processor is transmitting data at regular intervals
regardless of the RS232 connection. When the RS232 cable is
reconnected this data comes through OK.
I have gone so far as to reinitialize the UART after every
transmission, this has not helped. The only solution I have found is
to do a hardware reset or cycle the power, this is not acceptable to
our customers.
I have not been able to find anything in documentation regarding this
problem.
Has anyone had experience with this type problem?
By the way, has NXP technical support been abducted. They certainly
have become scarce.
Michael,
LPC2148 UART0 failure to receive
Started by ●October 17, 2008
Reply by ●October 17, 20082008-10-17
Reply by ●October 17, 20082008-10-17
On Fri, 17 Oct 2008 19:39:38 -0000, you wrote:
>--- In l..., Michael Coffee wrote:
>>
>> Noltstein
>>
>> Thanks for the reply. I have poked around in the interrupt routine.
> When this occurs no interrupt is generated and no data appears in the
>receive register.
Do you have the Line Status Interrupt enabled ?
>--- In l..., Michael Coffee wrote:
>>
>> Noltstein
>>
>> Thanks for the reply. I have poked around in the interrupt routine.
> When this occurs no interrupt is generated and no data appears in the
>receive register.
Do you have the Line Status Interrupt enabled ?
Reply by ●October 17, 20082008-10-17
mlcchemtrac wrote:
> I have gone so far as to reinitialize the UART after every
> transmission, this has not helped. The only solution I have found is
> to do a hardware reset or cycle the power, this is not acceptable to
> our customers.
>
> I have not been able to find anything in documentation regarding this
> problem.
>
> Has anyone had experience with this type problem?
DO you have the FIFO enabled?
Robert
> I have gone so far as to reinitialize the UART after every
> transmission, this has not helped. The only solution I have found is
> to do a hardware reset or cycle the power, this is not acceptable to
> our customers.
>
> I have not been able to find anything in documentation regarding this
> problem.
>
> Has anyone had experience with this type problem?
DO you have the FIFO enabled?
Robert
