Go to advanced search

by BertM
Mon Dec 10, 2012 12:50 pm
Forum: Wanted
Topic: Wanted - rPi Testing Device for Research Project
Replies: 18
Views: 5365

Re: Wanted - rPi Testing Device for Research Project

A Raspberry Pi is definitely overkill for this application, although it can of course be used to accomplish the same goal. For a such a device I would suggest using a simple ATmega microcontroller - like the Arduino - combined with a serial output accelerometer (such as the MMA8452Q ). Such microcon...
by BertM
Wed Apr 25, 2012 6:16 am
Forum: General discussion
Topic: Micro-USB Charger
Replies: 3
Views: 1566

Re: Micro-USB Charger

Bottom line: the voltage of the charger should be close to 5V (5.1V is ok), the current should be at least 700mA but you can go as high as you like.
by BertM
Wed Apr 25, 2012 6:04 am
Forum: Troubleshooting
Topic: A word of warning on using cheap Micro USB cables.
Replies: 23
Views: 8655

Re: A word of warning on using cheap Micro USB cables.

To all people that are suspecting a micro USB cable: measure the voltage between TP1 and TP2. If it's at least 4.9V, you can be pretty sure the cable is not faulty.
by BertM
Wed Apr 25, 2012 5:56 am
Forum: Troubleshooting
Topic: Not booting up, stuck on Power LED, no OK LED.
Replies: 48
Views: 13289

Re: Not booting up, stuck on Power LED, no OK LED.

<t>You are very right. I must have overlooked that core part. Considering the SoC is downstepping the voltage, one might guess that it should function on lower input voltages. But we don't know until it's been tested, of course. Anyone in to remove the voltage regulators onboard and tweaking all sep...
by BertM
Mon Apr 23, 2012 6:50 pm
Forum: Other projects
Topic: DEFINITE Raspi DSi screen list
Replies: 40
Views: 101888

Re: DEFINITE Raspi DSi screen list

<t>The parameters you name are very simple ones - a proper driver does not make assumptions on that (imagine what would happen if a DVI/VGA driver would do the same..) They are effictively just display modes and that has little to do with the device driver.<br/> <br/> It would be problematic if ever...
by BertM
Mon Apr 23, 2012 12:56 pm
Forum: General discussion
Topic: Mini-Pi
Replies: 19
Views: 4636

Re: Mini-Pi

<t>For most applications the RPi is small enough already. It is smaller than an Arduino, IIRC. And it does already have all kinds of benefits compared to a regular PC: it is about 100 times smaller, uses 200 times less power, makes no noise and can do everything a normal PC can. Do you really need t...
by BertM
Mon Apr 23, 2012 12:46 pm
Forum: General discussion
Topic: Tor
Replies: 4
Views: 999

Re: Tor

It should not be too hard to compile Tor for ARMv6. Why don"t you give it a try?
by BertM
Mon Apr 23, 2012 12:41 pm
Forum: Other projects
Topic: DEFINITE Raspi DSi screen list
Replies: 40
Views: 101888

Re: DEFINITE Raspi DSi screen list

<t>Yes, such an interconnect is a hurdle to overcome. I am quite sure however that someone with moderate soldering skills should be able to build one, provided he has the right connector and professionally made PCB. Keep in mind that such a board would have to provide the correct voltage levels as w...
by BertM
Mon Apr 23, 2012 1:36 am
Forum: Troubleshooting
Topic: Not booting up, stuck on Power LED, no OK LED.
Replies: 48
Views: 13289

Re: Not booting up, stuck on Power LED, no OK LED.

Any stable power source that can provide at least 4.4V should do.

None of the internal circuitry of the RPi uses 5V directly, only 3.3V. The 3.3V regulator ought to work perfectly fine when supplied with at least 4.4V.
by BertM
Mon Apr 23, 2012 1:30 am
Forum: Troubleshooting
Topic: Fixing power Stability Issues
Replies: 15
Views: 5287

Re: Fixing power Stability Issues

The ESR of this old capacitor may even be so high that you had better connected some AA batteries instead.

Fitting the RPi inside the capacitor is a better option IMHO
by BertM
Mon Apr 23, 2012 1:28 am
Forum: Troubleshooting
Topic: No power light anymore...
Replies: 5
Views: 2192

Re: No power light anymore...

<t>What do you mean by "flashing"? Irregular flashing, twice every second, once every 10 seconds?<br/> <br/> It will most likely be a short somewhere. The flashing you observe can be caused by<br/> <br/> - A bad connection<br/> <br/> - A faulty (external) power supply<br/> <br/> - An overheating RG2...
by BertM
Mon Apr 23, 2012 12:49 am
Forum: Troubleshooting
Topic: Capacitor broke off. :(
Replies: 22
Views: 9801

Re: Capacitor broke off. :(

<t>I am afraid that a through-hole mounted capacitor may even be more fragile, as a small amount of space between the base of the capacitor and the board may make the capacitor behave like a lever with respect to its pins, pulling the out effectively when the capacitor is bent.<br/> <br/> Adding a b...
by BertM
Mon Apr 23, 2012 12:39 am
Forum: Troubleshooting
Topic: USB hub sending power to Raspberry PI through USB port
Replies: 17
Views: 7743

Re: USB hub sending power to Raspberry PI through USB port

<t>The RPi will not need the full 700mA when connected to a powered hub: 280mA of that 700mA are reserved for supplying power to low-power USB devices, but a powered hub obviously does not need any power from the RPi.<br/> <br/> A hub that supplies 5V on its input is a strange hub, however. The reas...
by BertM
Mon Apr 23, 2012 12:30 am
Forum: Troubleshooting
Topic: Pi Don't ... No.1 in a series of things to not do...
Replies: 23
Views: 13220

Re: Pi Don't ... No.1 in a series of things to not do...

<t>It would be quite hard to destroy the RPi using only the ethernet connector, as there are magnetics involved. The RPi and the ethernet cable are more or less galvanically isolated. You can however fry the ethernet port, but such a part is replacable.<br/> <br/> If you really want to fry your Pi, ...
by BertM
Mon Apr 23, 2012 12:19 am
Forum: Other projects
Topic: DEFINITE Raspi DSi screen list
Replies: 40
Views: 101888

Re: DEFINITE Raspi DSi screen list

There are two datalanes exposed to the DSI connector.
by BertM
Mon Apr 23, 2012 12:14 am
Forum: General discussion
Topic: Adding a second SD-Card slot
Replies: 19
Views: 17945

Re: Adding a second SD-Card slot

<t>I recall once using a normal sized SD(HC) card in a project, that peeked at around 120mA, which was quite ridiculous in my opinion.<br/> <br/> Well, production of the necessary PCB should cost at most €1 (Seeed studio, 10pcs @ $10), a microSD connector can be found for less than $0.50, the only t...
by BertM
Sun Apr 22, 2012 11:22 am
Forum: General discussion
Topic: S2 and S5: Fit or no fit?
Replies: 13
Views: 33626

Re: S2 and S5: Fit or no fit?

<t>You can also buy those FFC/FPC/ZIF cables from Digikey, number HF15U-02-ND (replace 02 with 04/05/06/08/10/12/18 for cables with this length in inches). They are 15 conductor flat cables, starting at $3.15 unit price for 2 inch.<br/> <br/> Accompanying connectors can be bought from Farnell for 0,...
by BertM
Sat Apr 21, 2012 5:33 pm
Forum: General discussion
Topic: Adding a second SD-Card slot
Replies: 19
Views: 17945

Re: Adding a second SD-Card slot

Just a small sidenote: the maximum permissible current draw on the 3.3V of the GPIO is 50mA according to the wiki, so the board would have to incorporate a 5V -> 3.3V stepdown converter (or LDO linear regulator).
by BertM
Sat Apr 21, 2012 5:12 pm
Forum: Raspbian
Topic: HISTORY: The start of raspbian (Debian Hard Float (armhf) for RPi)
Replies: 613
Views: 367753

Re: Debian Hard Float (armhf) for RPi

Those are some pretty impressive numbers IMHO!
by BertM
Sat Apr 21, 2012 3:40 pm
Forum: General discussion
Topic: Adding a second SD-Card slot
Replies: 19
Views: 17945

Re: Adding a second SD-Card slot

<t>Knowing this:<br/> <br/> - The RPi hardware can speak SPI by itself, and SD cards speak SPI as well (in 1-bit mode)<br/> <br/> - The RPi GPIO provides 3.3V, SD cards use 3.3V<br/> <br/> It should therefore be almost trivial to add SD cards without having to resolve to bit-banging. Also, hardware ...
by BertM
Sat Apr 21, 2012 1:45 am
Forum: Other projects
Topic: Emulate USB mass storage device
Replies: 13
Views: 36957

Re: Emulate USB mass storage device

<t>If you can make the RPi talk the SD card protocol (the card side, to be precise) through its GPIO, you could just hook it up to any SD card reader you can get off eBay for $1.<br/> <br/> Considering the Broadcom SoC can interrupt on every single GPIO pin and the clock is entirely provided by the ...
by BertM
Sat Apr 21, 2012 1:35 am
Forum: Raspbian
Topic: HISTORY: The start of raspbian (Debian Hard Float (armhf) for RPi)
Replies: 613
Views: 367753

Re: Debian Hard Float (armhf) for RPi

<t>Just in case you are still looking for a dedicated server, the WebHostingTalk forums are a great place to look for cheap offers.<br/> <br/> If you're just going for disk space and bandwidth, you can have a 1.2GHz Celeron + 1TB disk + unmetered bandwidth @ 100Mbit at a price of $35 per month.<br/>...
by BertM
Fri Apr 20, 2012 11:51 pm
Forum: General discussion
Topic: LCD / LVDS Interface for Raspberry Pi
Replies: 81
Views: 126587

Re: LCD / LVDS Interface for Raspberry Pi

Just in case anyone is still wondering about the DSI interface, the connectors are populated. Two data lanes + one clock lane are exposed to the connector, as can be read in the schematics.
by BertM
Fri Apr 20, 2012 11:48 pm
Forum: General discussion
Topic: S2 and S5: Fit or no fit?
Replies: 13
Views: 33626

Re: S2 and S5: Fit or no fit?

Just FYI: both connectors are fit. See the schematics for pinouts.
by BertM
Fri Feb 17, 2012 9:08 pm
Forum: General discussion
Topic: LVDS Interface
Replies: 68
Views: 28042

Re: LVDS Interface

<t>sammy585 said: <br/> <br/> <br/> am confuse ...someone told me that LVDS is used to transfer lots of information very fast ...so its the LVDS for displays(images,videos) or is it for overall data ?<br/> <br/> <br/> LVDS stands for 'Low-voltage differential signaling' and is indeed an electronic w...

Go to advanced search