Questions on UARTs, and serial communication
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Joined: Fri Oct 19, 2012 5:11 am


Post by YahooArchive » Wed Oct 24, 2012 2:55 pm

> 2. Hyperterminal communication problem

Seems like Hyperterminal is asserting DTR which is keeping the
ARMexpress reset. I would expect any terminal program to work, with
XON-XOFF only required when downloading large programs. I've noticed
that a serial open in Windows XP toggles the DTR line so the
ARMexpress will get reset. The solution to Hyperterminal would be to
disconnect the DTR signal.

Posts: 1463
Joined: Fri Oct 19, 2012 5:11 am

Re: Hyperterm

Post by YahooArchive » Thu Oct 25, 2012 12:04 am

After a couple requests to allow legacy programs such as MatLab to
communicate with an ARMmite or ARMexpress using the serial port, that
capability has been added.

Many of these serial programs do not allow the user to control the DTR
and RTS lines, which are used to download and reset the ARMexpress
family boards. The normal configuration of the ARMexpress boards is
for both RTS and DTR to be idle (low voltage on RS232 port). This is
the default condition for a PC serial port. But these programs will
normally set DTR/RTS to the opposite state which stops the

So if you intend to control the ARMmite from one of these programs,
check the new helpfile page on the support page->Help HTML
files->Hardware Specs->USB use with MatLab, Hyperterm, TeraTerm

To program the ARMmite/express, TclTerm still is the way to do that,
and now it will support this configuration.

There is also a sample MinGW GCC program that controls a serial port
to show the basics of communicating with an ARMmite/express in the
files section of this group.

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Re: Hyperterm

Post by YahooArchive » Thu Oct 25, 2012 12:30 am

I've had some questions about Hyperterm and the ARMmite. Hyperterm
will not work with the ARMmite when its is configured normally, but
you can configure the ARMmite into "special" mode so that it will work
(see the help files hardware section on USB). I don't recommend this
unless you plan to use the ARMmite to communicate with legacy serial
programs that you cannot control the DTR/RTS lines.

In addition the TclTerm source and executeables have been updated on
the Support page. This source is actually the same as that contained
in the tools release (both C and BASIC). MakeItC uses TclTerm as the
Terminal tool, and BASICtools uses TclTerm as the core serial
communication channel. Both of these are "compiled" Tcl so they run
standalone on any PC with no other support files.

What probably isn't clear is TclTerm will also run standalone.
TclTerm was originally a terminal emulator written at Coridium to do
the function of Hyperterm, and then to control the ARMexpress. When
the ARMmite came out, TclTerm became more complex to manage compiling
programs on the PC and then uploading them to the ARMmite. Eventually
it morphed into BASICtools, but with the terminal functions extracted
back to TclTerm.tcl that is included at runtime by BASICtools.

So if you need a simple terminal emulator to communicate with an
ARMmite/express consider TclTerm (either source or executeable).

In the files section find USBcom.c which is C source written for MinGW
to run on a PC. I have started hacking in Linux and Mac extensions to
USBcom, though my progress will be very slow there (don't expect them
to be working now).

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Re: Hyperterm

Post by YahooArchive » Fri Jan 18, 2013 5:18 pm

>from help line
>But now I close BT, and fire up a simple terminal program (such as Hyperterm).
>Configured to COM3 correctly, and set to 19200,8,N,1.
>Hit RESET button on PRO - don't receive the prompt msg from it, nor can I
establish any communication

This has been covered before, but bears repetition, its also discussed in the
Help Files-


Our products use DTR and RTS to control reset and boot into C or BASIC. The
values we chose allow the board to run independent of a program on the PC.

But when you plug in a USB device, these lines are toggled during USB ID and are
dependent on a lot of factors (driver, OS, ...). The only solution to allow the
board to ignore these lines is to disconnect them. Easy to do on the PRO.

Or if you want to have a program on the PC control the board, there are C and
Tcl examples in the files section. Maybe someone will contribute a VB version
using MSCOMM.

In addition a standalone version of TclTerm has been uploaded to the files

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Joined: Fri Oct 19, 2012 5:11 am

Re: Hyperterm

Post by YahooArchive » Fri Jan 18, 2013 5:18 pm

Another option is to use Embedded Systems Academy's FlashMagic tool. As it says
on their website:

"Control the DTR and RTS RS232 signals to place the device into BootROM and
Execute modes automatically (requires hardware support)"


I use it to both to upload software to the ARMmite and use its terminal
emulation function to communicate with the USB/serial port of the ARMmite.

Chris Burrows

Armaide: LPC2xxx Oberon-07 Development System

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