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yaga_3967241
Level 3
Level 3
50 sign-ins 25 sign-ins 10 replies posted

Hi,

We are using PSoC LP5 with bootloader and bootloadable.

We have a situation that, PSoC power on another board(Let's call it core board) by setting a PsoC pin (pin30) high. When we call Bootloadable_Load() to enter bootloader mode in order to update PSoC SW, we found that the pin(pin30) changes to low for some time and the core board is powered down. The PSoC SW update is done from core board via I2C, with core board power down, there is no way to do the PSoC SW update apparently.

My question is that, when changing from bootloadable to bootloader using Bootloadable_Load(), is there a way to keep some pins unchanged? In my case, I would like to keep the pin(pin30) to  be high all the time.

Regards,

Winston

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1 Solution
RodolfoGL
Employee
Employee
250 solutions authored 250 sign-ins 5 comments on KBA

As Patrick mentioned before, all pins go to a high-Z state during a reset, so you will not be able to keep the state of a pin during this time. If your other product works at pin P12_6, it might be because the pin state was above the high threshold.

One thing you could do to minimize the power down of the other chip, it is to implement a dual-bootloader approach. In this case, you can receive a new image while executing the current application. Once you are done, you can swap the image, so the time the other device is down is minimum.

If that's not acceptable, there are ways to perform a swap of image without a full reset, but it adds some complexity in the system and some limitations what kind of updates you can do on the image.  

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pacr_284376
Level 5
Level 5
100 replies posted 10 solutions authored 50 sign-ins

Assuming pin30 is an enable signal for some kind of regulator for your 'core board'. 

On startup, I think all pins have high-impedance so you could just place a pull-up resistor on your board (between pin30 and power).

That way, you can still 'disable' this signal by pulling pin30 down but it does not switch on processor reset.

Patrick

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yaga_3967241
Level 3
Level 3
50 sign-ins 25 sign-ins 10 replies posted

It is a good idea to add some pull ups. But it is not allowed if I cannot provide sufficient reasons since actually there is a 100kohm pull down on the pin, and people start to question why it works so far for our other products.

I compared with the working case - in our other product, a different pin, P12_6, is used and it works fine. I observe that there is no dive pulse for that pin when entering bootloader mode; In out new board, we use P2_7. Is it possible that the different behavior is caused by that the two pins have different drive force?

Regards,

Winston

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Attachments are accessible only for community members.

Checkout, maybe you could change the "Power-On Reset" in the Reset-tab of the pin configuration. If I understand it correctly you can change the pin state during reset-state. But it has some limitations such as limited write cycles and port-wide.

See attachment

 

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RodolfoGL
Employee
Employee
250 solutions authored 250 sign-ins 5 comments on KBA

As Patrick mentioned before, all pins go to a high-Z state during a reset, so you will not be able to keep the state of a pin during this time. If your other product works at pin P12_6, it might be because the pin state was above the high threshold.

One thing you could do to minimize the power down of the other chip, it is to implement a dual-bootloader approach. In this case, you can receive a new image while executing the current application. Once you are done, you can swap the image, so the time the other device is down is minimum.

If that's not acceptable, there are ways to perform a swap of image without a full reset, but it adds some complexity in the system and some limitations what kind of updates you can do on the image.  

0 Likes