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Forum Index : Microcontroller and PC projects : Pico2 finally available in the US
| Author | Message | ||||
| al18 Senior Member  Joined: 06/07/2019 Location: United StatesPosts: 205 |
Finally got notification today from Mouser.com they have the Pico2 in stock at $5 and my back order is shipping today.https://www.mouser.com/ProductDetail/Raspberry-Pi/SC1631?qs=IKkN%2F947nfBrS4NBdUxzKQ%3D%3D |
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| gadgetjack Senior Member Joined: 15/07/2016 Location: United StatesPosts: 142 |
Mine too!! I got 5 coming..... |
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lew247 Guru  Joined: 23/12/2015 Location: United KingdomPosts: 1702 |
remember to use external pull up resistors on all inputs |
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Mixtel90 Guru Joined: 05/10/2019 Location: United KingdomPosts: 6778 |
The pull ups work. The pull downs are broken and they have to be external. So you can use active low inputs as before but not active high inputs without a pull down. Don't enable pull down resistors in MMBasic, just use the external ones. Also, don't assume that the ADC inputs are high impedance. They require more drive than the RP2040. Mick Zilog Inside! nascom.info for Nascom & Gemini Preliminary MMBasic docs & my PCB designs |
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| Volhout Guru Joined: 05/03/2018 Location: NetherlandsPosts: 4222 |
Mick, It is slightly different. The problem can occur with internal pulldown, or with NO internal pulldown. It has not been observed with internal pullup. So... SETPIN gp0,DIN 'has the problem SETPIN gp0,DIN,PULLUP 'has no problem SETPIN gp0,DIN,PULLDOWN 'has the problem. SETPIN gp0,FIN 'has the problem SETPIN gp0,CIN 'has the problem SETPIN gp0,PIN 'has the problem SETPIN gp0,DOUT 'has no problem SETPIN gp26,AIN 'does NOT have this particular problem When the RP2350 digital inputs are driven with an impedance higher than 10k (even if you do not use internal pullups) the input can get into a "locked" state, that is logic high to the ARM. But the level is around 2V. So with RP2350 use low impedance signals (10k maximum). This can be achieved by connecting a external pullup or pulldown resistor of 10k or less to each (used) input. Or, by driving the input pin from a logic gate, comparator etc. For I2C there is already a pullup required of 2k...5k, so there is not problem for I2C. Similar the PS2 keyboard and single wire devices. Volhout P.S. since the default power up configuration in MMBasic is DIN (digital input), all non-used pins can end up in this faulty state when left unconnected (floating). The fauty state also consumes power. It may be beneficial to program these unused pin in your MMBasic program as DIN,PULLUP. Then the pins are not "floating" and cannot end up in the faulty state. Edited 2024-09-26 18:58 by Volhout PicomiteVGA PETSCII ROBOTS |
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| Mixtel90 Guru Joined: 05/10/2019 Location: United KingdomPosts: 6778 |
Thanks. Volhout. :) Mick Zilog Inside! nascom.info for Nascom & Gemini Preliminary MMBasic docs & my PCB designs |
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| al18 Senior Member Joined: 06/07/2019 Location: United StatesPosts: 205 |
In my Mouser order, I added a pack of 25, 10K ohm 5% 1/4W resistors that cost just $0.75. On Mouser, search for 485-2784 . Looks like there are just 6 bags left. |
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| lew247 Guru Joined: 23/12/2015 Location: United KingdomPosts: 1702 |
GPIO RP2350-E9 Reference RP2350-E9 Summary Increased leakage current on Bank 0 GPIO when pad input is enabled Affects RP2350 A2 From the latest rp2350-datasheet.pdf |
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