my raspberry pi 2 MODEL B is not boot~!!!!!
I found that one resistor was missing next to the HDMI interface (R14).
If that's the reason, what's the model number? Thanks
- Burngate
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Re: I found that one resistor was missing next to the HDMI i
R14 isn't marked on the cut-down schematics, so we don't know what it does or its value.
It's interesting that, on the pictures I've looked at, it's not fitted on the Pi 3B, though it's there on the Pi 2B and the Pi B+
Are you sure it isn't booting?
Have you tried plugging into an analogue monitor, since Q2 seems to be connected to the CEC pin of the HDMI socket.
It's interesting that, on the pictures I've looked at, it's not fitted on the Pi 3B, though it's there on the Pi 2B and the Pi B+
Are you sure it isn't booting?
Have you tried plugging into an analogue monitor, since Q2 seems to be connected to the CEC pin of the HDMI socket.
Re: I found that one resistor was missing next to the HDMI i
For this Pi2B V1.2, using BCM2837, R14 does not appear to be fitted -Burngate wrote:It's interesting that, on the pictures I've looked at, it's not fitted on the Pi 3B, though it's there on the Pi 2B
http://raspi.tv/wp-content/uploads/2016 ... 2_1500.jpg
But it does appear to be fitted for this Pi2B V1.1 using BCM2836 -
https://tr1.cbsistatic.com/hub/i/2015/0 ... -pi2-1.jpg
- Burngate
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Re: I found that one resistor was missing next to the HDMI i
It seems unlikely (though not impossible) that changing the SoC meant that resistor wasn't required.
Perhaps Q2 has been changed for a different type?
Perhaps Q2 has been changed for a different type?
Re: I found that one resistor was missing next to the HDMI i
I'd hazard a guess that R14 is the same pullup resistor as R15 on the CMIO boards, on the HDMI_CEC line. There it is a 27K pullup to 3V3 on the CMIO Rev 1.2, but not fitted on the CMIO Rev 3.0.
- Burngate
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Re: I found that one resistor was missing next to the HDMI i
So it is possible that the newer SoC has a built-in pull-up, negating the need for R14/15
Re: I found that one resistor was missing next to the HDMI i
Nah, the CMIO3 works with the CM1. Maybe they use an internal pullup, or it just isn't needed, WJDK.