AN134 M U L T I P L E - D E V I C E JTAG C O N F I G U R A T I O N I N T H E S I L I C O N L A B S IDE 1. JTAG Chain Configuration To configure the Multiple-Device JTAG Chain feature of the Silicon Labs IDE you need to provide the following information: The number of devices before and after the target. The number of bits in the IR registers of the devices before and after the target. In the Silicon Labs IDE, select Connection Options... from the Options menu. In the Connection Options window, press the JTAG Chain Configuration button to open the Multi-device JTAG Programming dialogue box shown below. In versions of the IDE previous to v2.0, press the key combination ctrl+shift+m to open the Multidevice JTAG Programming dialogue box. Figure 1. Multi-Device JTAG Programming Dialogue Box 2. Order of Devices See Figure 2 to determine the order of the devices in the chain. Device #0 is before Device #1 and Device #2 Device #1 is before Device #2 and after Device #0. Device #2 is after Device #1 and Device #0. TCK TMS TDO TDI JTAG Controller TCK TDO TMS TDI JTAG Device #0 TCK TDO TMS TDI JTAG Device #1 TCK TDO TMS TDI JTAG Device #2 Figure 2. Typical JTAG Chain Connection Rev. 1.2 11/04 Copyright © 2004 by Silicon Laboratories AN134 AN134 3. Example This example uses three devices placed in the order shown on the previous page with the following configuration: Device #0 has a 16 bit IR register. Device #1 has an 8 bit IR register. Device #2 has a 16 bit IR register. If the Silicon Labs device that you want to program is Device #0, enter the following configuration information into the Multi-device JTAG Programming window as shown in Figure 3: There are 0 devices before the target. There are 2 devices after the target. There are 0 IR bits before the target’s IR register. There are 24 IR bits after the target’s IR register. Figure 3. Multi-Device JTAG Programming Example 2 Rev. 1.2 AN134 DOCUMENT CHANGE LIST Revision 1.1 to Revision 1.2 Updated last paragraph in "1. JTAG Chain Configuration" on page 1. Rev. 1.2 3 AN134 CONTACT INFORMATION Silicon Laboratories Inc. 4635 Boston Lane Austin, TX 78735 Tel: 1+(512) 416-8500 Fax: 1+(512) 416-9669 Toll Free: 1+(877) 444-3032 Email: [email protected] Internet: www.silabs.com The information in this document is believed to be accurate in all respects at the time of publication but is subject to change without notice. Silicon Laboratories assumes no responsibility for errors and omissions, and disclaims responsibility for any consequences resulting from the use of information included herein. Additionally, Silicon Laboratories assumes no responsibility for the functioning of undescribed features or parameters. Silicon Laboratories reserves the right to make changes without further notice. Silicon Laboratories makes no warranty, representation or guarantee regarding the suitability of its products for any particular purpose, nor does Silicon Laboratories assume any liability arising out of the application or use of any product or circuit, and specifically disclaims any and all liability, including without limitation consequential or incidental damages. Silicon Laboratories products are not designed, intended, or authorized for use in applications intended to support or sustain life, or for any other application in which the failure of the Silicon Laboratories product could create a situation where personal injury or death may occur. Should Buyer purchase or use Silicon Laboratories products for any such unintended or unauthorized application, Buyer shall indemnify and hold Silicon Laboratories harmless against all claims and damages. Silicon Laboratories and Silicon Labs are trademarks of Silicon Laboratories Inc. Other products or brandnames mentioned herein are trademarks or registered trademarks of their respective holders. 4 Rev. 1.2