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Plasmamac

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Joined: 31/01/2019
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Posted: 02:35pm 29 Jul 2025

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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

stanleyella

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Joined: 25/06/2022
Location: United Kingdom
Posts: 2566

Posted: 03:19pm 29 Jul 2025

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great!

matherp
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Joined: 11/12/2012
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Posted: 03:24pm 29 Jul 2025

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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.

Plasmamac

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Posted: 03:37pm 29 Jul 2025

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Ok , thanks for the hint

Plasma

Mixtel90

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Joined: 05/10/2019
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Posted: 03:53pm 29 Jul 2025

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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.

Mick

Zilog Inside! nascom.info for Nascom & Gemini
Preliminary MMBasic docs & my PCB designs

stanleyella

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Posted: 11:06pm 29 Jul 2025

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Mixtel90

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Posted: 06:43am 30 Jul 2025

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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!

Mick

Zilog Inside! nascom.info for Nascom & Gemini
Preliminary MMBasic docs & my PCB designs

JanVolk
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Joined: 28/01/2023
Location: Netherlands
Posts: 247

Posted: 02:13pm 30 Jul 2025

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

Regards,

Jan.

stanleyella

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Posted: 08:17pm 30 Jul 2025

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derrr???

JanVolk
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Joined: 28/01/2023
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Posted: 09:31pm 30 Jul 2025

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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.

toml_12953
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Joined: 13/02/2015
Location: United States
Posts: 442

Posted: 11:06pm 30 Jul 2025

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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.

EDNEDN
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Joined: 18/02/2023
Location: United States
Posts: 155

Posted: 11:46pm 30 Jul 2025

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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.

JanVolk
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Joined: 28/01/2023
Location: Netherlands
Posts: 247

Posted: 12:16am 31 Jul 2025

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

Regards,

Jan.

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