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cable rs232 lpc-p2148 with PC

Started by davideciannamea July 7, 2010
Hello.

The RS232 cable on Olimex LPC-p2148, must be crossed or straight?
The card must communicate with Pc, with HyperTerminal in Windows.

Thanks.

An Engineer's Guide to the LPC2100 Series

On Wed, 2010-07-07 at 07:22 +0000, davideciannamea wrote:
> Hello.
>
> The RS232 cable on Olimex LPC-p2148, must be crossed or straight?
> The card must communicate with Pc, with HyperTerminal in Windows.

Hi,

Not owning a lpc-p2148 myself but after looking at the schematic
I would say a straight cable.
You can also find this information yourself by looking at the
schematic and/or testing the sud-d9 pins with a Volt meter.
On the PC side pin 2 of the male sub-d9 connector is input and
pin 3 is output. (pin 5 being ground)

roelof

--- In l..., "davideciannamea" wrote:
>
> Hello.
>
> The RS232 cable on Olimex LPC-p2148, must be crossed or straight?
> The card must communicate with Pc, with HyperTerminal in Windows.
>
> Thanks.
>
If the olimex board has a plug (sticky out pins) then you'll need a cable with pins 2+3 crossed and 5 straight through. If it has a socket (holes) then you'll need a straight through cable

Alternatively a quick look at the Olimex schematic diagram would clear this up.

--
Tim Mitchell
ok thanks but for programming, i use JTAG ARM-USB-TINY. I want to see the output in HyperTerminal or similar programs. The rs232 cable (straight) is always the same????

--- In l..., "cfbsoftware1" wrote:
>
> --- In l..., "davideciannamea" wrote:
> >
> > The RS232 cable on Olimex LPC-p2148, must be crossed or straight?
> > The card must communicate with Pc, with HyperTerminal in Windows.
> > I was testing one of these boards only yesterday. I used a straight through cable and the terminal emulator function of FlashMagic. For programming, the male end of the cable was connected to the female RS232_0/ICSP socket on the Olimex board. The female end was connected to the male RS232 socket of a PC. Both dipswitches were set to ON for programming AND automatic reset / running the software using FlashMagic.
>
> Regards,
> Chris Burrows
> CFB Software
>
> Astrobe: LPC2xxx Oberon-07 Development System
> http://www.astrobe.com
>

--- In l..., "davideciannamea" wrote:
>
> ok thanks but for programming, i use JTAG ARM-USB-TINY. I want to see the output in HyperTerminal or similar programs. The rs232 cable (straight) is always the same????
>

Yes - for that particular board. Just skip my references to programming. FlashMagic has a dual purpose - programming and terminal emulation. Using FlashMagic as a terminal emulator on the PC is similar to using any other terminal emulator. I just find it (and most other terminal emulators!) less quirky to use than HyperTerminal.

If you want some background information about when you need / don't need to use a straight cable connection see:

http://en.wikipedia.org/wiki/Null_modem

Chris.

Help!!!

--- In l..., "davideciannamea" wrote:
>
> Hello.
>
> The RS232 cable on Olimex LPC-p2148, must be crossed or straight?
> The card must communicate with Pc, with HyperTerminal in Windows.
>
> Thanks.
>

--- In l..., "davideciannamea" wrote:
>
> The RS232 cable on Olimex LPC-p2148, must be crossed or straight?
> The card must communicate with Pc, with HyperTerminal in Windows.
>

I was testing one of these boards only yesterday. I used a straight through cable and the terminal emulator function of FlashMagic. For programming, the male end of the cable was connected to the female RS232_0/ICSP socket on the Olimex board. The female end was connected to the male RS232 socket of a PC. Both dipswitches were set to ON for programming AND automatic reset / running the software using FlashMagic.

Regards,
Chris Burrows
CFB Software

Astrobe: LPC2xxx Oberon-07 Development System
http://www.astrobe.com