TPLD1201-DGS-EVM: IO9 output H during startup?

user4616635

Prodigy 90 points

Part Number: TPLD1201-DGS-EVM

Tool/software:

Hi,

I think that IO9 output H pulse during startup EVM. Is it true?

Both DFFs has L intial state, so will start L outputs for IO6 and IO7.

But after clicking [CONFIGURE] at the InterConnect Studio, IO6 is H, and IO7 is L, actually.

It seems only DFF0 receive clock pulse from IO9 during startup sequence.

8 months ago

0 user4616635 8 months ago

Prodigy 90 points

Sorry. I'm misunderstanding.

It seems, IN0 make H pulse during startup. Not IO9.

0 Ian Graham 8 months ago in reply to user4616635

TI__Genius 9401 points

Hello,

Since the flip flop is generating an invented output, if it is set to start up in the low state, the initial output will be a high pulse. If you want it to start up outputting low with an inverted output, the initial state should be high.

You should be able to see this in the simulation tool.

Hope this helps!

Ian

0 user4616635 8 months ago in reply to Ian Graham

Prodigy 90 points

Dear Ian,

Thank you for detailed explanation, but I'm afraid this is not FF issue, I think.

Changed FF to not iverted output as follows:

IO9 and IN0 are EVM 2 buttons with 1k pull down. So I guess 2 FF outputs continue L, during startup.

Simulation result is as I think:

But after clicking [CONFIGURE], EVM IO7 ( is LED7 ) is turned ON.

That means dff1 changed status. IN0 generated H pulse to dff1.

Here is zipped syscfg file:

TPLD1201_EVM_button_test.zip

+1 Ian Graham 8 months ago in reply to user4616635

TI__Genius 9401 points

Hi,

I checked with the programming team and you are correct. After the device is programmed, the GPI line is sent a HIGH signal. This is intentional and is necessary for programming, so there is no way to prevent it.

Best,

Ian

0 user4616635 8 months ago in reply to Ian Graham

Prodigy 90 points

Dear Ian,

I understand your reply. Thank you.

Best,

Yasunori Okutsu

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TPLD1201-DGS-EVM: IO9 output H during startup?