Certain test procedures and production environments require the use of a cable longer than the typical 9-inch flat ribbon cable typically included with P&E hardware interfaces. Extending the cable length requires special considerations for signal integrity, crosstalk, and electromagnetic interference. Simply using a longer cable without understanding these topics will usually produce a setup that does not work reliably, if at all.

If it is necessary to use a longer cable, P&E recommends using a shielded jacketed cable . This cable configuration is excellent at reducing crosstalk as well as minimizing electromagnetic interference from other devices. Further improvement can be obtained if the wires are also arranged in twisted pairs. Shielded USB cables are inexpensive and easy to rework. The four wires provided can be used to create a cable for the standard 6-pin BDM header used by many Freescale microprocessors.

In general, these guidelines should be followed for all cables between the target microprocessor and the P&E hardware interface:

1. Use the shortest cable possible

    

2. Use shielded cable configurations to reduce parasitic effects

    

3. Lower the communication frequency.

For certain architectures, this can be configured in software by the user. For other architectures, the communication speed is only dependent on the processor's bus frequency. Reducing the bus frequency (ie. disabling the PLL) should improve results.

P&E's UNIT Library Interface Routines for the 68HC16 now support the USB Multilink Interface for the 68HC16 architecture. The UNIT Library comes in the form of a DLL with example interface code for Microsoft Visual Studio as well as Borland Delphi. All the calls in the DLL are documented so that other development environments can also access the calls.

The UNIT library allows a customer to create a Windows application on the PC which directly controls the target 68HC16 processor via one of P&E's hardware interfaces (the CABLE1632 Parallel Port Interface and now additionally the USB Multilink Interface). Using the library, the Windows application can reset the 68HC16 processor, read/write memory, load code, step, run, and much more! The libary is perfect for creating test, update, and diagnostic applications.

Unit libraries are available for most all Freescale architectures. Details can be seen here.

P&E offers a set of In-Circuit Debuggers that are packed with powerful scripting features. Whether you are stepping through a couple of lines of assembly code or debugging a C-level source, P&E's toolset can help you get the job done. P&E's In Circuit Debuggers are designed with repeatable test and debugging procedures in mind. Therefore, the user can completely automate software tests by creating a macro script and saving the outcome in a log file. As a result, the user can avoid hours of repeatedly setting up software and firmware tests.

Click through to view a small demonstration of how the built in macro commands can be used to create and perform a repeatable firmware test on a 9S08AW60 processor...

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Boston, MA - P&E Microcomputer Systems announces that it has extended the support of its PowerPC Nexus tools to include Freescale’s new MPC56XX devices. This set of in-circuit debuggers, FLASH programmers, and hardware debug interfaces now supports both MPC55xx and MPC56xx devices, offering a comprehensive solution for Freescale’s advanced automotive microprocessors.

Boston, MA - P&E Microcomputer Systems announces the release of the DEMOJM development board, available through Freescale. The DEMOJM is a low-cost development system that supports Freescale MC9S08JM60 and MCF51JM128 64LQFP microcontrollers. It consists of a DEMOJM Base Board, a DC9S08JM60 Daughter Card and a DC51JM128 Daughter Card. P&E’s Embedded Multilink circuitry on the DEMOJM board allows the processor connected to the DEMOJM to be powered, debugged, and programmed via USB from a PC.