We have developed a customized board using reference schematic of SAMA5D27 XULT.
We have used SAMA5D21 processor on our board.
By default according to FUSE value UART 1 IOSET 1 is selected for debug messages. (messages like "RomBOOT").
UART 1 IOSET 1 means PD2 and PD3 pins.
But these pins are not available on SAMA5D21.
Basically i want to use JTAG on my board, but JTAG (SAM-ICE) is not recognizing my processor.
It constantly shows me error as,
"Could not measure total IR length. TDO is constant HIGH."
I am using J-Link tool from segger with SAM-ICE.
So first i want to make sure that processor is soldered properly and working fine.
I can confirm this if "RomBOOT" message is printed on debug port.
But since default debug port is not there, i have to change it through FUSE.
But JTAG is not recognizing processor, hence i can not change fuse bit.
I read in datasheet of SAMA5D2, in the section "Chip Access Using JTAG Connection" (section 14.6.4), that '#' needed to sent from console to enable the JTAG.
I don't have USB port/pins out on my board.
I have not flashed any code into memory yet. I have just powered on the board.
There is no any bootable program present on board except ROM code.
So the question is,
How do i enable the JTAG on my board, if it is not enabled by default?
which is the default debug port on SAMA5D21, since the default pins are not available?
If JTAG is enabled by default, then what might be the reason for continuous
"Could not measure total IR length. TDO is constant HIGH." message from SAM-ICE?