TMS320F28335: Uniflash Issue

Ethan Held22

Part Number: TMS320F28335
Other Parts Discussed in Thread: UNIFLASH,

Hi All,

I had a question regarding use of Uniflash with the TMS320F28335.

A TMS320F28335ZJZQ is used in my board. It is a new board, so after testing some code, I erased the code in the DSP with the software "UniFlash". However, I found the pin C6 (GPIO46/XA6), the GPIO port, still output 3.3V after the erasing.

It happened to all three boards that we tried this on, could that be "not-erasing the code completely" or some other issues?

Thanks,

Ethan

over 8 years ago

0 Brett Larimore over 8 years ago

TI__Guru 57255 points

Hi Ethan,

I'm afraid there's not enough information shared to be sure that there is a problem.

Please note that, on this device family, GPIO12-87 are configured to come up as GPIO inputs with weak internal pull-up circuits enabled, after reset. As a result, what they are seeing may be expected.

Please see:

http://processors.wiki.ti.com/index.php/General_Purpose_IO_%28GPIO%29_FAQ_for_C2000#Q:_Are_the_pull-ups_on_pins_that_can_be_used_as_ePWM_outputs_enabled_or_disabled_on_reset.3F

http://www.ti.com/lit/sprufb0
(see definition of GPAPUD-GPCPUD registers and their value after reset)

Thank you,
Brett

0 Ethan Held22 over 8 years ago in reply to Brett Larimore

TI__Prodigy 680 points

thanks for the feedback!

One follow up question, does this hold true for the F2811 family of devices as well? (internal pull ups on the GPIO pins)

0 Brett Larimore over 8 years ago in reply to Ethan Held22

TI__Guru 57255 points

Hi Ethan,

The wiki page describes the situation for the F281x separately. Please take a look at it.

(note that most GPIO on the F281x have pullups, and only a handful do not. The information on which have pullups can be found in the device datasheet (look for PU in the pin descriptions table))

Thank you,
Brett

C2000™︎ microcontrollers

C2000 microcontrollers forum

TMS320F28335: Uniflash Issue