J-Link / J-Trace User Guide (UM08001) - Microcontrollers

5.6 Connecting multiple J-Links / J-Traces to your PC
You can connect up to 4 J-Links / J-Traces to your PC. In this case, all J-Links / J-
Traces must have different USB-addresses. The default USB-address is 0.
In order to do this, 3 J-Links / J-Traces must be configured as described below. Every
J-Link / J-Trace need its own J-Link USB driver which can be downloaded from
www.segger.com.
This feature is supported by J-Link Rev. 5.0 and up and by J-Trace.
5.6.1 How does it work?
USB devices are identified by the OS by their product id, vendor id and serial number.
The serial number reported by J-Links / J-Traces is always the same. The product id
depends on the configured USB-address.
• The vendor id (VID) representing SEGGER is always 1366
• The product id (PID) for J-Link / J-Trace #1 is 101
• The product id (PID) for J-Link / J-Trace #2 is 102 and so on.
A different PID means that J-Link / J-Trace is identified as a different device, requiring
a new driver. The driver for a new J-Link device will be installed automatically.
The sketch below shows a host, running two application programs. Each application
communicates with one ARM core via a separate J-Link.
Application
Instance 1
USB
J-Link
1
JTAG
ARM1
Target hardware 1
Host (PC)
Application
Instance 2
ARM2
J-Link / J-Trace (UM08001) © 2004-2010 SEGGER Microcontroller GmbH & Co. KG
USB
J-Link
2
JTAG
Target hardware 2
103