Hacker News Board Hacker News, browsed like a classic message board
Live data from Hacker News

Raspberry Pi Model A+ Board

cnx-software.com

Post reply on HN
Print view View original

41–50 of 51 posts

Re: Raspberry Pi Model A+ Board

#41

Post by pingec »

maguirre wrote: post #2

I love the RPi and what it has done to introduce computing/programming/linux to more people. However I can't get past how unreliable booting from an SD card has been for me. I know reliability depends heavily on the SD card used and on the quality of board socket but I am disappointed that Rev 2 of the board did not come with the option of on-board flash.

I am of a similar opinion. Here's my story.

I wanted to use the r.pi for storing sensor data sent from an arduino over serial port. The arduino worked rock stable but there were so many problems with the r.pi. Let me describe some of them.

First had a problem of r.pi freezing every few days. This was the first revision. The community said I must have had a bad SD card or a bad power supply or a bad USB hub. I was determined to make it work. I went ahead and bought 3 more power supplies and 2 USB hubs and 5 SD cards all of different but recommended models for use with r.pi. The freezes did not go away. At this point the community just started shrugging or saying I must be doing something wrong. This got me very frustrated.

So one day I ordered a new r.pi (model A), plugged in place of the old one and freezes were gone, ha!

However, there were still problems I could not work out. For example running lcd4linux with dpf-ax display on USB would make the r.pi freeze/crash (with kdb session spawned on r.pi serial port) after a few hours.

Another problem was data corruption on power loss. For example I had a FAT formatted USB flash stick to which I was logging data. And one day after an electricity blackout I find 80% of the files on that stick corrupt. I don't know why that would happen, I would expect maybe the active files being affected but not the files that had not been read nor written to since months before. Here is an example of data corruption [1]. Can anyone explain how this can happen? Any ideas?

I addressed the lcd4linux problem by buying a beaglebone black which has no such problems. I am still scared that one day my data will corrupt again so now I am logging straight to github.

To summarize, I think r.pi was definitely not worth the time nor the money I spent on it. Although I really wanted to, I could not make it work in the end.

[1] http://pingec.si/corruption.JPG

Re: Raspberry Pi Model A+ Board

#42

Post by iwwr »

101914 wrote: post #20
maguirre wrote: post #2

I love the RPi and what it has done to introduce computing/programming/linux to more people. However I can't get past how unreliable booting from an SD card has been for me. I know reliability depends heavily on the SD card used and on the quality of board socket but I am disappointed that Rev 2 of the board did not come with the option of on-board flash.

Just to give a different perspective, I think booting from SD card is my favorite aspect of the RPi (although I do not disagree with your comment). This is because I find it gives me easier flexibility in switching between kernels with embedded userlands. I run my OS from RAM with only tmpfs for secondary storage, and I make my SD cards read-only. I do not try to use an SD card like a HDD, but I am aware that many pe…

Would r-pi work better with 1gb or more of ram, or would that push the price into a prohibitive range?

What about usb3 or sata/esata?

Re: Raspberry Pi Model A+ Board

#43

Post by Narishma »

Aqwis wrote: post #18

Is small size the only thing the A/A+ has over the B/B+ board? Is size really such a big issue for prototyping boards like the Raspberry Pi?

Smaller size, smaller price and smaller power consuption. Also smaller memory, no ethernet and less USB ports.

Re: Raspberry Pi Model A+ Board

#44

Post by maguirre »

pingec wrote: post #41
maguirre wrote: post #2

I love the RPi and what it has done to introduce computing/programming/linux to more people. However I can't get past how unreliable booting from an SD card has been for me. I know reliability depends heavily on the SD card used and on the quality of board socket but I am disappointed that Rev 2 of the board did not come with the option of on-board flash.

I am of a similar opinion. Here's my story. I wanted to use the r.pi for storing sensor data sent from an arduino over serial port. The arduino worked rock stable but there were so many problems with the r.pi. Let me describe some of them. First had a problem of r.pi freezing every few days. This was the first revision. The community said I must have had a bad SD card or a bad power supply or a bad USB hub. I was det…

Data corruption during power loss has also been one of my biggest headaches with it comes to single board computers. I don't think I can say this is an issue that afflicts RPis only. However if you attempt to log data into the same device that you boot from you are asking for trouble imho. Someone else in this thread mentioned running the OS from RAM. I didn't know this was an option but I need to do some reading on how to do this. In your case though, I think backing up to a remote device is about the only sensible way to attack the data corruption problem.

Re: Raspberry Pi Model A+ Board

#45

Post by rebootthesystem »

dnr wrote: post #38
rebootthesystem wrote: post #27

Does anyone know of a Raspberry Pi type board (low cost, Linux capable, good hardware graphics) with HDMI input and output suitable for image processing?

Maybe look at a Cubox-i4 Pro? (Or the equivalent Hummingboard.) Depends what you mean by image processing.

That's the question, isn't it. I can't define it very well right now. We have a board we designed in house that uses a large FPGA for a range of basic real time image processing on 1920 x 1080 video. It's about ten years old. It'd be nice to be able to replace it with a software based platform and Python.

Also, it seems this has the same issue as other similar boards: No HDMI input.

Re: Raspberry Pi Model A+ Board

#46

Post by rebootthesystem »

KaiserPro wrote: post #36
rebootthesystem wrote: post #27

Does anyone know of a Raspberry Pi type board (low cost, Linux capable, good hardware graphics) with HDMI input and output suitable for image processing?

Something like the intel NUC is possibly your only real choice, unless you want to work really hard porting libraries. It reasonably cheap, 10watts at full tilt, and has 2 real core (plus 2HT) I use one for my openCV things, that need real time(ish) performance.

No HDMI input on this board. I suppose we could look into doing our own HDMI in to PCIe mini board to go with it. Not that hard, just a lot of work.

Re: Raspberry Pi Model A+ Board

#47

Post by whiskers »

iwwr wrote: post #42
101914 wrote: post #20

Earlier quoted context omitted.

Just to give a different perspective, I think booting from SD card is my favorite aspect of the RPi (although I do not disagree with your comment). This is because I find it gives me easier flexibility in switching between kernels with embedded userlands. I run my OS from RAM with only tmpfs for secondary storage, and I make my SD cards read-only. I do not try to use an SD card like a HDD, but I am aware that many pe…

Would r-pi work better with 1gb or more of ram, or would that push the price into a prohibitive range? What about usb3 or sata/esata?

The SOC doesn't support more than 512MB of RAM (or USB3). Raspberry Pi is built to a price point above all else - you could keep adding/upgrading features but you'd just end up way out of their target price.

Re: Raspberry Pi Model A+ Board

#48

Post by JamesH65 »

custardcream wrote: post #8
maguirre wrote: post #2

I love the RPi and what it has done to introduce computing/programming/linux to more people. However I can't get past how unreliable booting from an SD card has been for me. I know reliability depends heavily on the SD card used and on the quality of board socket but I am disappointed that Rev 2 of the board did not come with the option of on-board flash.

Been lurking for a bit. Was hoping to say hello with a constructive comment but I have to jump in here. I bought a Pi model B for my daughter. Nothing but terrible unreliability. Booting problems as you state, power problems with the USB ports, random hangs and crashes and problems getting half of the devices recommended to work. I kind of expected that for the money but the thing that really pissed me off was when I…

As one of the mods on the Pi forum, I can categorically say - if you had a post deleted and your username banned, it was down to your behaviour, NOT criticism.

We simply do not delete posts or accounts unless the poster is overly rude or clearly trolling. The forum is frequented by a lot of children, so it is essential that things are kept polite.

This is reflected in the number of people banned from the forum in the last 3 years which is less than 50 (excluding spammers), and the excellent reports back we get from people of the high quality of forum etiquette and postings.

So, I would have to take issue with your comments on the forum. If you were banned, you brought in on yourself.

Can I also suggest that if your daughters school has some Pi's that are not being used, then the school send a teacher to a Picademy session - they are two day courses, free, held at the Raspberry Pi offices, specifically for teachers to give them ideas on how to use Pi's in the classroom. Lack of use usually means lack of knowledge of what is possible, rather than lack of ability in the device itself.

Re: Raspberry Pi Model A+ Board

#49

Post by JamesH65 »

rebootthesystem wrote: post #45
dnr wrote: post #38

Earlier quoted context omitted.

Maybe look at a Cubox-i4 Pro? (Or the equivalent Hummingboard.) Depends what you mean by image processing.

That's the question, isn't it. I can't define it very well right now. We have a board we designed in house that uses a large FPGA for a range of basic real time image processing on 1920 x 1080 video. It's about ten years old. It'd be nice to be able to replace it with a software based platform and Python. Also, it seems this has the same issue as other similar boards: No HDMI input.

Due to DRM issues, HDMI input on any device is rare. You can buy HDMI input chips that convert HDMI to CSI-2 so they can be plugged in to a camera socket - I've got a prototype that works on a Raspberry Pi. But it won't work for encrypted HDMI in, so you are very limited in what you can take in. And enabling DCHP is a very expensive proposition.

Re: Raspberry Pi Model A+ Board

#50

Post by custardcream »

JamesH65 wrote: post #48
custardcream wrote: post #8

Earlier quoted context omitted.

Been lurking for a bit. Was hoping to say hello with a constructive comment but I have to jump in here. I bought a Pi model B for my daughter. Nothing but terrible unreliability. Booting problems as you state, power problems with the USB ports, random hangs and crashes and problems getting half of the devices recommended to work. I kind of expected that for the money but the thing that really pissed me off was when I…

As one of the mods on the Pi forum, I can categorically say - if you had a post deleted and your username banned, it was down to your behaviour, NOT criticism. We simply do not delete posts or accounts unless the poster is overly rude or clearly trolling. The forum is frequented by a lot of children, so it is essential that things are kept polite. This is reflected in the number of people banned from the forum in the…

Total unadulterated bullshit.

My first post (perhaps this was a grave mistake), I gave a concise rundown of all of the problems that I had during the process of provisioning the thing and explained my dissatisfaction. I was not rude or condescending. In fact I asked for suggestions and offered improvement advice. Perhaps advice (from someone who's being working in the embedded systems sector for 20 years isn't real advice?). If I'd bought a MacBook Pro and it had the same functional problems, I'd say the same things about it. If I bought a vacuum cleaner that didn't work, I'd say the same things about it.

One of the problems was that the thing wouldn't output on composite at all (we didn't have a device handy that took HDMI in) and that I complained about the fact you have to poke keys in the dark to configure video (no video output) when you don't know if the hub or keyboard is working properly. Then that started the whole process of hoop jumping to get Linux running on it. Perhaps you remember me now?

I had about 4 replies to my comment, two of which were backing up my claims and one which was actually helpful.

Then the next thing I know, I went to reply to the post by someone trying to be helpful to say thanks and bang, no account. That's poor moderation and trying to hide dissatisfaction and criticism which is not acceptable. That's entirey your problem as a moderator.

Well lack of use in their case is that they don't have the time to do the hoop jumping when it's pretty easy to fire up a python interpreter from an MSI package on a windows machine to get the same results. I thoroughly approve of this; the first experience of proper computer science education shouldn't be hoop jumping and trying to work out how to get the thing working. Much like the BBC Micro, it should be plug it in, turn it on and open the User Guide.

90% of people fall at the first hurdle and you made it a very high one.

In absolutely no way would I recommend it to them.

Now I'm going to take a stab: The Picademy thing sounds much like the old school "big vendor" sales approach. Come see our products and you'll buy and market them for us. Sorry but no banana. I can't recommend the Raspberry Pi in any way and would not enable any promotion of them.

Post reply on HN