In SX Microcontrollers, SX/B Compiler and SX-Key Tool, g_daubach wrote:

Several other threads deal with problems that may, or may not be caused by a defective SX-Key.

Here is a test you may perform to check your SX-Key:

Make sure that the SX-Key IDE is not running, or any other application that makes use of the COM port, the SX-Key is connected to.

Make sure that the SX-Key is connected to this COM port via a serial cable, and also make sure that the SX-Key is powered, i.e. it is plugged to a target system's 4-pin header in correct orientation, with power applied to the target system.

Launch HyperTerminal or any other equivalent communications program, and configure it to use the COM port, the SX-Key is connected to, set the baud rate to 57,600, 8 data bits, no parity, 1 stop bit, no handshake. When the terminal program has an option to echo the input characters, turn this option off.

Next, enter the following text in the terminal program (without the quotes but in correct case): "SX-Key". As you type each character, it should be immediately displayed in the terminal's receive window. This is because the SX-Key hardware is designed to directly echo back each received character by hardware, i.e. not through the on-board SX20. So, you would receive such echos even when the SX-Key is not powered..

When you don't receive these echos, it is most likely that you have selected (or connected the SX-Key to) the wrong COM port, or the serial cable between the PC and the SX-Key might be (broken, or not a straight-through cable), or that any of the SUB-D 9 connectors has bad contact. In this case, fix such problems, before continuing.

Immediately after you have entered the last "y" of the "SX-Key" string, the SX-Key should respond with "SX-Key???" where the three "???" are any arbitrary values. 

When you get this answer, you can be sure that the hardware to connect to the SX-Key is in good shape, and that the SK-Key's on-board SX20 is operating - at least does it correctly handle the communication with the PC.

There still may be other SX-Key components broken, like the on-board 5/12V DC/DC converter for the programming voltage (Vpp), or the on-board clock generator. To my experience, this might only happen when you put the SX-Key under extreme stress, like supply voltage above 7 Volt, or a heavy electrostatic discharge. 

More than once did I plug the SX-Key on a target system's 4-pin header the wrong way but even this did never "fry" the SK-Key. Even plugging to or un-plugging from a powered target system did not kill any of my SK-Keyes. Nevertheless, it is good practice to un-power a system before plugging/un-plugging components, and this includes the SX-Key as well.

---------- End of Message ----------


You can view the post on-line at:
http://forums.parallax.com/forums/default.aspx?f=7&p=1&m=102421

Need assistance? Send an email to the Forum Administrator at forumadmin@parallax.com

The Parallax Forums are powered by dotNetBB Forums, copyright 2002-2005 (http://www.dotNetBB.com)