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Posted: 02:35pm
29 Jul 2025
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Plasmamac
Guru


Rp2350 A are now 5v tolerant
Rp2354 has now 2 MB on chip flash
And a new SDK


Edited 2025-07-30 01:19 by Plasmamac
Plasma
 
Posted: 03:19pm
29 Jul 2025
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stanleyella
Guru


great!
 
Posted: 03:24pm
29 Jul 2025
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matherp
Guru

Be careful with the 5V tolerance - THERE IS NO CHANGE

See the release info

It is just a documentation change. THE RP2350  MUST STILL BE POWERED BEFORE 5V IS APPLIED TO ANY OF ITS PINS.
 
Posted: 03:37pm
29 Jul 2025
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Plasmamac
Guru


Ok , thanks for the hint
 
Posted: 03:53pm
29 Jul 2025
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Mixtel90
Guru


It will withstand 5V on the GPIO pins PROVIDING THAT THE PICO IS POWERED UP FROM AT LEAST 3V3. You can't safely connect 5V signals if the Pico is unpowered as you'll damage it. So it's NOT TTL compatible, it's 5V tolerant under specific circumstances.
 
Posted: 11:06pm
29 Jul 2025
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stanleyella
Guru


 
Posted: 06:43am
30 Jul 2025
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Mixtel90
Guru


Where you have to be very careful is with a USB-TTL converter when you are using a USB version of the PicoMite firmware. The pullup resistors on the data lines are often to the 5V supply from the USB port so you mustn't connect them to a PicoMite unless you either fit level shifting or can guarantee that the signals will never exceed 3V6 at the absolute max. Some converters allow you to select 5V or 3V3, but test them before you connect as those links don't always do what you expect!
 
Posted: 02:13pm
30 Jul 2025
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JanVolk
Senior Member

https://www.raspberrypi.com/news/rp2350-a4-rp2354-and-a-new-hacking-challenge/

Regards,

Jan.
 
Posted: 08:17pm
30 Jul 2025
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stanleyella
Guru


derrr???
 
Posted: 09:31pm
30 Jul 2025
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JanVolk
Senior Member

RP2350A and RP2350B A2 -> A4

Today, we’re happy to announce the immediate availability of a new A4 stepping, which addresses the vast majority of these issues.

What is fixed in A4?

Firstly, and most importantly for general users, we’ve fixed Erratum 9. A small tweak was applied to the pad macro to eliminate the undesirable leakage in the high side of the pad; this leakage gives rise to the large negative-going excursion in the current-against-voltage trace for A2 below. As a result, external resistors are no longer required to pull inputs low, though they may safely be retained in existing designs.

Errata 20, 21 and 24 are boot ROM security vulnerabilities discovered in the course of the RP2350 Hacking Challenge. These have been fixed in the A4 boot ROM, which, in addition, implements a variety of new defensive strategies to reduce the likelihood of future exploits. We have also taken this opportunity to fix a number of minor functional errata in the boot ROM.

Erratum 16 is a security vulnerability, again discovered in the course of the RP2350 Hacking Challenge, which relates to the behaviour of the OTP when power is removed during a read operation. This has been fixed through changes to the wrapper circuitry surrounding the OTP macro.

Erratum 3, which relates to the behaviour of the GPIO_NSMASK registers on 60-pin RP235x parts, has also been fixed.

Regards,

Jan.
 
Posted: 11:06pm
30 Jul 2025
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toml_12953
Guru

  JanVolk said  https://www.raspberrypi.com/news/rp2350-a4-rp2354-and-a-new-hacking-challenge/

Regards,

Jan.


FYI: The 2350DIL I just received from JLCPCB uses an A2.
 
Posted: 11:46pm
30 Jul 2025
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EDNEDN
Senior Member

  JanVolk said  RP2350A and RP2350B A2 -> A4

What is fixed in A4?

Firstly, and most importantly for general users, we’ve fixed Erratum 9. A small tweak was applied to the pad macro to eliminate the undesirable leakage in the high side of the pad; this leakage gives rise to the large negative-going excursion in the current-against-voltage trace for A2 below. As a result, external resistors are no longer required to pull inputs low, though they may safely be retained in existing designs.



Does this mean the GPIO lock up problem becomes a non-issue once A4 is being used everywhere?     I've been waiting to get any RP2350's until the GPIO lock up problem goes away.
 
Posted: 12:16am
31 Jul 2025
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JanVolk
Senior Member

https://www.elektormagazine.com/news/rp2350-a4-stepping

Regards,

Jan.
 


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