Hi,
I am designing a board with Texas Instrument's TM4C123GH6PM microcontroller and I have found contradictory information between the TI's TM4C12x JTAG guide and SEGGER J-Link user guide.
In the first one, "Using TM4C12x Devices Over JTAG Interface", it uses a series resistor in pin1(VTref), a pull down resistor in TDO line, no pull-up nor pull-down on TDI line and series resistors in TMS, TCK, TDO and TDI (screen shot attached)
On the other hand, the SEGGER J-Link user guide says that VTref (Pin1) MUST NOT HAVE a series resistor, TDO line has no pull-up or down, TDI has to be pulled to a defined state and it says nothing about lines' series resistors (screen shot attached).
In summary, what interface should I use in my design?
[img]https://forum.segger.com/index.php?page=Attachment&attachmentID=2573&h=b82f4444b09a75cc6889bf6eb2279c9adeb4ce07[/img]
[img]https://forum.segger.com/index.php?page=Attachment&attachmentID=2571&h=ea87e4908bbc09b4ae38dd883c5f59c7b094ab4a[/img]
[img]https://forum.segger.com/index.php?page=Attachment&attachmentID=2572&h=dd744240f797a8e42761a190757cd84ee2d1a97f[/img]
I am designing a board with Texas Instrument's TM4C123GH6PM microcontroller and I have found contradictory information between the TI's TM4C12x JTAG guide and SEGGER J-Link user guide.
In the first one, "Using TM4C12x Devices Over JTAG Interface", it uses a series resistor in pin1(VTref), a pull down resistor in TDO line, no pull-up nor pull-down on TDI line and series resistors in TMS, TCK, TDO and TDI (screen shot attached)
On the other hand, the SEGGER J-Link user guide says that VTref (Pin1) MUST NOT HAVE a series resistor, TDO line has no pull-up or down, TDI has to be pulled to a defined state and it says nothing about lines' series resistors (screen shot attached).
In summary, what interface should I use in my design?
[img]https://forum.segger.com/index.php?page=Attachment&attachmentID=2573&h=b82f4444b09a75cc6889bf6eb2279c9adeb4ce07[/img]
[img]https://forum.segger.com/index.php?page=Attachment&attachmentID=2571&h=ea87e4908bbc09b4ae38dd883c5f59c7b094ab4a[/img]
[img]https://forum.segger.com/index.php?page=Attachment&attachmentID=2572&h=dd744240f797a8e42761a190757cd84ee2d1a97f[/img]