Voltage changes, CM1 vs. CM3+

StereoPi hardware discussion
Post Reply
xanatos
Posts: 4
Joined: Thu Apr 25, 2019 7:02 pm

Voltage changes, CM1 vs. CM3+

Post by xanatos » Sun May 12, 2019 11:14 pm

Very confused on this wording:

On the DIY Ninjas page at https://wiki.stereopi.com/index.php?tit ... as_Section

The power jumper info states the following (emphasis mine):

Compute Module 1 needs 5V power for VBAT, and CM3/CM3+ needs 3.3V VBAT.

By default StereoPi is tuned to provide 5V voltage for CM3 series support.

Note that these two statements are contradictory. AND... I just tried powering up my StereoPi with the CM3+ module installed and gave it 5.0Vdc, and got three solid red LEDs and no boot.... did I just fry it?

Please confirm for me whether the CM3+ requires 3.3Vdc jumper on the StereoPi or 5.0Vdc jumper - the datasheet for the CM3+ states a VBAT of 5.0v, but lists several other supply voltages that need to be present, including 3.3Vdc, 1.8Vdc, etc., so I am still confused and don't wish to try something randomly before verifying again.

Thanks for the clarification. Looking forward to running these up.... once I know I can do so without frying my CM3+ units.

Dave

User avatar
Realizator
Site Admin
Posts: 299
Joined: Tue Apr 16, 2019 9:23 am
Contact:

Re: Voltage changes, CM1 vs. CM3+

Post by Realizator » Mon May 13, 2019 7:13 am

xanatos wrote:
Sun May 12, 2019 11:14 pm
Very confused on this wording:

On the DIY Ninjas page at https://wiki.stereopi.com/index.php?tit ... as_Section

The power jumper info states the following (emphasis mine):

Compute Module 1 needs 5V power for VBAT, and CM3/CM3+ needs 3.3V VBAT.

By default StereoPi is tuned to provide 5V voltage for CM3 series support.
Dave, thank you for your notice!
I've fixed this Wiki page.
By default, StereoPi has 5V kernel power voltage, intended for CM3/3+ series modules. You need to change it only for CM1.

Also please notice, that for power change you need to do soldering. Onboard jumper do another job - puts StereoPi to the firmware upload mode. It will not boot in this mode, but will provide access to eMMC if you use eMMC equipped CM.
xanatos wrote:
Sun May 12, 2019 11:14 pm
Note that these two statements are contradictory. AND... I just tried powering up my StereoPi with the CM3+ module installed and gave it 5.0Vdc, and got three solid red LEDs and no boot.... did I just fry it?
Nope, you did not fry it.
Check list:
1. Are you using eMMC or non-eMMC module? If it is eMMC enabled module, please do not insert microSD card, as both eMMC and microSD uses the same SDIO lines. We kept reference approach used in official Pi devboard. Just upload Linux image to eMMC, as described in our Wiki.
2. Please remove jumper if you installed it. I mean jumper on pins marked by "A" here.
xanatos wrote:
Sun May 12, 2019 11:14 pm

Please confirm for me whether the CM3+ requires 3.3Vdc jumper on the StereoPi or 5.0Vdc jumper - the datasheet for the CM3+ states a VBAT of 5.0v, but lists several other supply voltages that need to be present, including 3.3Vdc, 1.8Vdc, etc., so I am still confused and don't wish to try something randomly before verifying again.

Thanks for the clarification. Looking forward to running these up.... once I know I can do so without frying my CM3+ units.

Dave
No, you do not need to do any fixes if you use CM3/3+ series Compute Module.
Eugene a.k.a. Realizator

xanatos
Posts: 4
Joined: Thu Apr 25, 2019 7:02 pm

Re: Voltage changes, CM1 vs. CM3+

Post by xanatos » Mon May 13, 2019 10:56 am

That's great, very happy to hear I haven't fried my CM3+. Appreciate your fast response as well! Looking forward to my next window of opportunity to upload to eMMC and try again. Thanks!

Post Reply