Hi
-Can i insert another JTAG device (Xilinx CPLD) in the chain ? Will i still be able to debug / download if thre are more devices chained ? (i think JTAG is intended to do that).
-Can the ULINK JTAG be used to drive cpu pins directly in order to test the connected HW ?
Johan
Q1: to my ken, fpga uses the configuration jtag and mcu uses a debug jtag, may be different.
Q2: jlink can be as it provides the jlinkarm dll. i don't know ulink has such dll.
ULINK supports multiple devices in a JTAG chain. It autodetects devices in the chain and automatically selects the CPU for debugging (manual configuration of the chain and selection of the device is also possible).
ULINK can be used to debug a CPU (also Flash programming) but not to drive CPU pins directly (Boundary Scan).
Hi Jagaert , I tried it 4 weeks before with an LPC2468 and Xilinx FPGA Spartan3 you can make a chain with it.
Xilinx Jtag tool works great and detects the devices in chain automatic and can program it. I thing if anybody writes a bdsl file you can program the LPC too.
Segger Jlink works but you must config the chain parameter manual and then it works only with the Segger tools (see later).
ULINK Keil failed with autodetect. No Device found.
ULINK with manual config like Jlink fails. The range you can enter for Parameter is only 16bit and you need 32 bit. If you try to enter a 16 Bit Value Keil crashes with click the add Button. So I think no one use this feature.
But for professional series you need a chain and one Tool. I use to JLINK it is the better probe with software breakpoints and more speed with debug.
You can try Scanseer software http://www.scanseer.com to drive/sense pins of cpu or cpld on your board. However, Scanseer does not support ULINK as a JTAG connection, but it works with Segger J-Link, FTDI FT2232 based adapters and a couple others.