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by jackokring
Sun Jan 03, 2016 1:32 pm
Forum: HATs and other add-ons
Topic: 3.5" Touch Screen TFT LCD RPi B+
Replies: 10
Views: 42732

Re: 3.5" Touch Screen TFT LCD RPi B+

https://github.com/swkim01/waveshare-dt ... verlay.dts is the overlay for waveshare 3.5", but I'm not sure if it's in the overlays provided as default. Check in the overlays folder of the boot partition. It also needs to be setup in a config file.
by jackokring
Sun Jan 03, 2016 12:56 am
Forum: Interfacing (DSI, CSI, I2C, etc.)
Topic: STICKY: Optional interfaces (I2C, I2S, SPI) and Device Tree
Replies: 128
Views: 140325

Re: Optional interfaces (I2C, I2S, SPI) and Device Tree

A few changes on the SPI as follows, but I know there are errors. /dts-v1/; /plugin/; / { compatible = "brcm,bcm2835", "brcm,bcm2836", "brcm,bcm2708", "brcm,bcm2709"; [email protected] { target = <&spi0>; frag0: __overlay__ { #address-cells = <1>; #size-cells = <0>; pinctrl-0 = <&spi0_pins &spi0_cs_pins>; ...
by jackokring
Sun Jan 03, 2016 12:20 am
Forum: Interfacing (DSI, CSI, I2C, etc.)
Topic: SPI and chip select pins
Replies: 13
Views: 32234

Re: SPI and chip select pins

viewtopic.php?f=44&t=98318&start=25 covers multi (>2) CS. With overlays. And a bit or 'reg' diddling and a full map should works. ...
by jackokring
Sat Jan 02, 2016 9:44 pm
Forum: Interfacing (DSI, CSI, I2C, etc.)
Topic: SPI and chip select pins
Replies: 13
Views: 32234

Re: SPI and chip select pins

So is it possible to remove the ALT0 status of a pin and get it to revert to an active 1, while keeping the SPI running? A 0b11 match then gives a third SPI, and 0b00 blows up your board (a possibility which SHOULD be regulated) unless there is a priority circuit, but why not NOT make is CS4? Or is ...
by jackokring
Sat Jan 02, 2016 7:52 pm
Forum: HATs and other add-ons
Topic: Makibes 3.5" LCD with Touch (GPIO used/free)
Replies: 1
Views: 785

Re: Makibes 3.5" LCD with Touch (GPIO used/free)

Ok, found out it was a repackaged waveshare 3.5", and so easy to find details on. Unused pins found. Ummm, an SPI future issue. ... Question: Both CE signals are used, so it then comes down to switching SPI usage. I have looked over the overlay file, and it seems both SPI get disabled. This is fine ...
by jackokring
Fri Jan 01, 2016 9:35 pm
Forum: HATs and other add-ons
Topic: small screen
Replies: 4
Views: 748

Re: small screen

There are some composite video car reversing monitors which work, cheap and run from 5v even though they are specified at 12v. Only QVGA resolution though. VGA=640*480, so 320*240, and some lost lines if over scan not used.
by jackokring
Thu Dec 31, 2015 9:09 pm
Forum: Beginners
Topic: Using a tft display
Replies: 2
Views: 363

Re: Using a tft display

by jackokring
Thu Dec 31, 2015 9:04 pm
Forum: HATs and other add-ons
Topic: Makibes 3.5" LCD with Touch (GPIO used/free)
Replies: 1
Views: 785

Makibes 3.5" LCD with Touch (GPIO used/free)

I've ordered one for a model A+, and will have use for the extended GPIO. But, what of the original 26 pins are not used? Not too essential, but could be useful to know before hand for planning. There is enough net info to set it up, but little on what it leaves as spare.
by jackokring
Mon Jul 28, 2014 1:02 am
Forum: HATs and other add-ons
Topic: Preliminary B+ HAT (Hardware Attached on Top) docs/specs
Replies: 106
Views: 37073

Re: Preliminary B+ HAT (Hardware Attached on Top) docs/specs

Having read the docs, I'm also curious about this. It seems to imply that if you're only using the first 26 pins, then you should leave ID_SD floating, but if you're using any of the last 12 pins you have to connect ID_SD to GND. Does this mean that if people are 'prototyping' and connecting jumper...
by jackokring
Sun Jul 27, 2014 12:36 pm
Forum: Off topic discussion
Topic: BCM employees
Replies: 32
Views: 5391

Re: BCM employees

An NDA such as this usually includes a never disclose clause without being informed of a change. There is often a non compete clause too.
by jackokring
Sat Jul 26, 2014 10:10 pm
Forum: Troubleshooting
Topic: Raspi B+ distorted sound
Replies: 17
Views: 3056

Re: Raspi B+ distorted sound

But an implementable easy unity voltage gain amplifier with a low output impedance, and a high input impedance is very slightly under unity gain in voltage, and so is an attenuator of voltage. The fact that a simple potential divider potentiometer circuit prefixes the circuit amplifier, provides the...
by jackokring
Sat Jul 26, 2014 9:47 pm
Forum: Troubleshooting
Topic: Raspi B+ distorted sound
Replies: 17
Views: 3056

Re: Raspi B+ distorted sound

An attenuator is not too complicated, and is in effect a very small power amplifier, as the impedance effect of a potentiometer needs buffering. An attenuator is, by definition, not an amplifier! Current amplifier, voltage unity buffer, volts times current equals power. Therefore POWER amplifier. E...
by jackokring
Sat Jul 26, 2014 7:53 pm
Forum: Troubleshooting
Topic: Raspi B+ distorted sound
Replies: 17
Views: 3056

Re: Raspi B+ distorted sound

Quantization distortion appears as noise too. The principal of noise shaping "moves" this to unnoticeable ultrasonic or less sensitive frequencies, increasing the apparent quantization resolution in the ear sensitive frequencies. An attenuator is not too complicated, and is in effect a very small po...
by jackokring
Sat Jul 26, 2014 5:31 pm
Forum: Compute Module
Topic: Pins RX/TX Serial UART
Replies: 4
Views: 1627

Re: Pins RX/TX Serial UART

I think the default UART or console would be the best option as this needs minimal configuration.
by jackokring
Sat Jul 26, 2014 5:07 pm
Forum: Off topic discussion
Topic: BCM employees
Replies: 32
Views: 5391

Re: BCM employees

I'd employ you all if only I could afford it. Anyone interested in self employed unpaid intern work from home work? Only joking. :D But seriously I think you could all get together and develop some highly commercial add-ons for the Pi.
by jackokring
Sat Jul 26, 2014 4:57 pm
Forum: Troubleshooting
Topic: Raspi B+ distorted sound
Replies: 17
Views: 3056

Re: Raspi B+ distorted sound

So you say the video comes out on the microphone wire. is the microphone still connected, as this may inject video signals into the audio depending on the resistance (impedance) of the microphone and the ground wiring. EDIT: it is also perhaps due to the pi using 12 bit sound (IIRC), and using no no...
by jackokring
Sat Jul 26, 2014 3:13 pm
Forum: Troubleshooting
Topic: Raspi B+ distorted sound
Replies: 17
Views: 3056

Re: Raspi B+ distorted sound

This sounds like a problem with quantization noise, and perhaps driving a low impedance causing current limiting, (and supply rail intermodulation distortion, but this would get louder as increase in volume, but maybe a mask by sound effect).

EDIT: It's not a buzzing effect due to an earthing issue.
by jackokring
Fri Jul 25, 2014 5:38 pm
Forum: Raspbian
Topic: 24th July rpi-update jessie failed
Replies: 0
Views: 436

24th July rpi-update jessie failed

After doing a long update yesterday to make my image B+ compatible, I then tries an rpi-update. It failed with an unexpected end of stream in the archive. A new bootloader was installed via the regular apt-get update, and I'm not sure if the rpi-update is needed, but just informing you.
by jackokring
Fri Jul 25, 2014 4:05 pm
Forum: HATs and other add-ons
Topic: Preliminary B+ HAT (Hardware Attached on Top) docs/specs
Replies: 106
Views: 37073

Re: Preliminary B+ HAT (Hardware Attached on Top) docs/specs

Looks good, just in the last FAQ, should quantity be quality? The rest is very readable.
by jackokring
Wed Jul 23, 2014 2:57 pm
Forum: HATs and other add-ons
Topic: Preliminary B+ HAT (Hardware Attached on Top) docs/specs
Replies: 106
Views: 37073

Re: Preliminary B+ HAT (Hardware Attached on Top) docs/specs

But if you use 28 pins, you can get it to auto-configure on a B+.
by jackokring
Tue Jul 22, 2014 11:31 pm
Forum: General discussion
Topic: Raspberry Pi google coder shutdown
Replies: 17
Views: 2548

Re: Raspberry Pi google coder shutdown

Is this a "grey goo" problem? Do you need the code saved? And if yes to both, I can't ever tell you. :D
by jackokring
Tue Jul 22, 2014 11:23 pm
Forum: General discussion
Topic: Happy Pi Approximation Day!
Replies: 10
Views: 1821

Re: Happy Pi Approximation Day!

Is next months better? I might wait and see. :D
by jackokring
Tue Jul 22, 2014 6:01 pm
Forum: HATs and other add-ons
Topic: Preliminary B+ HAT (Hardware Attached on Top) docs/specs
Replies: 106
Views: 37073

Re: Preliminary B+ HAT (Hardware Attached on Top) docs/specs

mikronauts wrote:toupe's?
:D :D :D :D :D

Bobbles?
by jackokring
Tue Jul 22, 2014 4:52 pm
Forum: Other
Topic: REALLY fast os?
Replies: 34
Views: 24121

Re: REALLY fast os?

A hibernate mode perhaps?
by jackokring
Tue Jul 22, 2014 4:50 pm
Forum: General discussion
Topic: Original or clone?
Replies: 20
Views: 3161

Re: Original or clone?

The Apollo 14 Pi?

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