TM4C129XNCZAD: Flashing binary to Micro controller using Tiva Bootloader via UART

If you have avoided the presence of a JTAG header (and pull-up Rs) - that "saving" (most always) proves unwise.

A far better (safer) approach sees one providing "component footprints" for, "Ten Pin Mini-JTAG header & pull-ups."     (it proves likely - that at some point - the "speed, ease & convenience" of such JTAG/SWD Access will be much appreciated...)

There is a detailed, "ROM Bootloader document" which provides the key detail you seek.     (IIRC - there is a key GPIO pin which "triggers" the UART to respond as you desire...)

Friend/poster "BP" has MUCH more familiarity w/your device.     (firm/I never employ '129 - M7s and far faster M4s - "lurk" nearby...)

BTW - if your desire to "Avoid JTAG Access due to some other things" - essentially targets, "Code Security" - may I offer you an "Exceptional Deal" - on a bridge spanning NYC's east river?    (this "deal" is very HOT)

Even if - and especially if - you disable or otherwise confound JTAG - our group can have your code w/in 30 minutes!     (if doubtful - ask this (or similar other) vendors to "Guarantee in WRITING - that your code may be fully/properly, "Secured!")     NONE will accept such challenge!     Is it reasonable to "expect" that a (near) 10 (USD) MCU (in bulk) can prove, "Secure?"      There ARE MCUs which impose "higher costs to defeat" yet most have also "yielded their secrets" to a smart, experienced, well equipped/motivated/financed team - whose capabilities, budget & motivation FAR EXCEED that of the (alleged) "code protectors!"

Firm/I know of "few other things" which (come near) to justifying "Avoiding JTAG!"

cb1_mobile said:

Firm/I know of "few other things" which (come near) to justifying "Avoiding JTAG!"

Agreed. Avoiding JTAG cannot really be justified by security considerations. I doubt it can be justified by I/O considerations either.

Robert

Yeah, I'm not taking that wager.

Robert

Sorry 'bout that mon ami.    (the rubber hoses - employed during my "beat-down" - got me to "give up" your (often frozen) GPS coordinates.    (staff here were told - in my absence - that RCMP (mounties) were "on their way!"    Fear not - there IS heat in those cells - and your "cb1-gift pack" includes IAR, J-Link, and "cubic-zirconium edged" (diamond-like) saw-blade.     (those "unkind" may link my "surplus of cubic zirconium" to "failed marriage proposals"    (there HAVE been a few - but "Hey - I'm selective ... and the "Chi. Futures Market" priced "cubic Z" so that it could NOT be resisted!)"

At 20 lines of "C code" - and 20mm/day "cell-bar cutting" - you should have, "Completed the boot-loader AND "hacked your path to freedom" by "mid-Spring" - at the latest...     (wonder if "Les Femmes Blonde/Canadian" can "tell the difference" between "cubic Z" and its "more expensive" look-alike?...)

sajmal baheesh said:

In my case , internal flash is empty and BOOTCFG is not programmed.

So is it possible to update it via UART in this situation? , If internal flash is empty, does it automatically goes into update mode?

Yes if RBIAS resistor has been installed for EMAC0 configured or not. Otherwise one must remove MOSC crystal and ROM bootloader then depends on internal PIOSC. Note my comment above post GPIO port H3 seems to ring a bell other forum posters have past mention success.  Datasheet BOOTCFG REG 68 indicates H7 defaults though TM4C1294NCZAD ends at H3.

As poster presents NO "real reason" for the "Avoidance of JTAG" - should things not "Run to Perfection" - is he NOT destined to become, "Dead in the water?"

Earlier it was wagered that his "dislike" for JTAG stemmed from "security concerns" - yet a far larger concern proves, "MCU recovery when JTAG is absent!"      As so (very) few succeed w/any Bootloader in "One Go" - poster embarks upon a (very) slippery slope - does he not?