Connect 2+ Chips With Emulator

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Abstract

Now many customers use DM36x + DM6437 to implement Intelligent IPNC. When they design JTAG connection, they meet many problems about how to design and how to set in CCS configuration. This document describes these details.

Mixed Devices Topography

Because DM36x is device with RTCK but DM6437 is device without RTCK, we use Mixed Devices Serial Topography.
If your design contains both devices with RTCK pins and those without an RTCK pin, regardless of the topography, the TCK signal of those devices without an RTCK pin must be driven with the RTCK from those devices with RTCK since these devices must govern the XDS RTCK rate.
Figure shows mixing devices with RTCK in a series topography and those without RTCK. Those devices without an RTCK are grouped together at the end of the scan chain, and their TCK signals are driven with the RTCK from the last device in the scan chain with a RTCK.
Figure Multiprocessor Mixed Device Types (with and without RTCK) Series Topography

Jtag 01.JPG

This figure only shows connections without regard to buffering or termination that may also be required. For additional details on connecting multiple devices

Example Hardware connection

Hardware connection SCH example is as follow:

Jtag 02.JPG

How to configure CCS setup

After implement hardware connection, next step is configuring CCS setup. Because there are two devices on JTAG path so you should set two paths separately to let JTAG know which is first device and which is second. Device with RTCK should be the first device, in this case is DM365.
If the device to be added is an FPGA or an unsupported processor, it is necessary to know its JTAG IR path length and add a device of type BYPASS.

The procedure to configure CCSetup for system above:

  • With CCSetup open, select the tab Create Board, choose the emulator used (in this example a SD510USB is used) and click Add
  • Give the connection a name (in this example it is dm365plusDm6437_xds510usb). Click Next and click Finish to use the standard I/O port (0x510 if only one emulator is connected to your PC)
  • Now add each internal JTAG structure for DM365:
    • Select the connection dm365plusDm6437_xds510usb in the left screen.
    • Select ICEPICK_C. Click Add and then Next twice (DM365 has only one subpath and does not need a GEL file in the ICEPICK_C). At the last screen, type 0x10 as the port number and click Finish.
    • Select Subpath_0 in the left screen.
    • Select ARM9. Click Add and optionally give it a meaningful name (ARM9_365 in this example). Add a GEL script if necessary and click OK.
  • Now add each internal JTAG structure for DM6437:
    • Select the connection dm365plusDm6437_xds510usb in the left screen
    • Select ICEPICK_C. Click Add and then Next twice (DM365 has only one subpath and does not need a GEL file in the ICEPICK_C). At the last screen, type 0x10 as the port number and click Finish.
    • Select Subpath_1 in the left screen.
    • Select C6400PLUS. Click Add and optionally give it a meaningful name (in this case it was left as default). Add a GEL script if necessary and click OK.

The example above in CCS setup is shown below:
Jtag 03.JPG

Summary

This document is only for Mixed device JTAG connection. For more JTAG connection information please see http://processors.wiki.ti.com/index.php/XDS_Target_Connection_Guide as reference.

Note: this paper is summit by Dong, Feng. Modifications to the setup process were done by Souza, Rafael.