On Sat, Mar 02, 2002 at 05:38:39AM +0530, Harishankkar wrote: > Thanx. Okay Strong ARM cannot do it. But my general doubt is that is it > possible to access core registers of any processor via JTAG ?. I am talking > in reference how using the freeze pin of the MPC 823E or the Power PC series > we can get the values of the internal registers etc. Is it a JTAG interface > like thing?
The JTAG interface is primerily there for what is called "Boundary Scan" testing. This is where you manipulate the logic levels on one chip and read the state of signals on another chip thereby checking that all the chip pins are soldered to the board, and the board doesn't contain any bad connectivity. JTAG was never designed as a software debugging tool. The fact that some processors in the market have this non-standard ability is just an added bonus. No StrongARM processor supports any kind of debugging, whether it is reading any on-board register, writing any on-board register, interogating the CPU state, reading the CPU state, provinding the CPU with instructions, and so on and so forth. It is only capable of the "test" mode of operation where it is being used to test the board connectivity. I think this has been explained in this thread many times over already. Let's not get stuck here. Let's move on. _______________________________________________ http://lists.arm.linux.org.uk/mailman/listinfo/linux-arm http://www.arm.linux.org.uk/armlinux/mailinglists.php Please visit the above addresses for information on this list.
