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by rpdom
Wed Apr 25, 2018 5:02 pm
Forum: Raspbian
Topic: Bash script: double ascii stream to hex .. and back
Replies: 14
Views: 176

Re: Bash script: double ascii stream to hex .. and back

PeterO wrote:
Wed Apr 25, 2018 5:00 pm
B.Goode wrote:
Wed Apr 25, 2018 4:45 pm
Now we need a wrapper that converts 30323441 into 024A before invoking .hexstr.sh
What is the algorithm for that conversion ? I can see no relation between 30323441 and 024A.
PeterO
ASCII Hex values
0x30 = "0"
0x32 = "2"
0x34 = "4"
0x41 = "A"
by rpdom
Wed Apr 25, 2018 3:36 pm
Forum: Troubleshooting
Topic: Raspberry PI 3 "Under Voltage"
Replies: 9
Views: 205

Re: Raspberry PI 3 "Under Voltage"

I have a number of USB chargers, cables and power banks with uUSB connectors that just don't mate properly with any of my Pi's (Too loose) That's why I gave up using them. I have the opposite experience. Every charger/power supply/whatever with MicroUSB connectors have had no problems connecting to...
by rpdom
Wed Apr 25, 2018 2:47 pm
Forum: General discussion
Topic: Determining 3B board age
Replies: 2
Views: 112

Re: Determining 3B board age

I believe the numbers 1610, 1637 and 1643 are the manufacturing date codes. 2016 weeks 10, 37 and 43.
by rpdom
Wed Apr 25, 2018 3:47 am
Forum: Camera board
Topic: What resistor value is C3 on the camera?
Replies: 4
Views: 136

Re: What resistor value is C3 on the camera?

It should be a 1uF capacitor, according to the schematics which have just been released https://www.raspberrypi.org/documentati ... a2_2p1.pdf
by rpdom
Tue Apr 24, 2018 5:13 pm
Forum: General discussion
Topic: SenseHat Callibration for Compass
Replies: 11
Views: 288

Re: SenseHat Callibration for Compass

MMrmcnich wrote:
Tue Apr 24, 2018 4:34 pm
Ah I always just update and upgrade I never repeat update after.
Yes. Usually that is fine. This is an exceptional case due to the particular upgrade.
by rpdom
Tue Apr 24, 2018 1:55 pm
Forum: General discussion
Topic: Enable Predictable names
Replies: 19
Views: 306

Re: Enable Predictable names

root@hitchhiker:~ # dpkg -l | grep raspi-config What is that "grep" doing in there other than to make more work for your poor raspberry? pi@raspi7:~ $ dpkg -l raspi-config Desired=Unknown/Install/Remove/Purge/Hold | Status=Not/Inst/Conf-files/Unpacked/halF-conf/Half-inst/trig-aWait/Trig-pend |/ Err...
by rpdom
Tue Apr 24, 2018 12:18 pm
Forum: Troubleshooting
Topic: Official touchscreen is upside down.
Replies: 6
Views: 137

Re: Official touchscreen is upside down.

I got it to work, however, the viewing angles are worse with the display like this, can you put the display in the other way around? That's the reason the image appeared upside down. The original design of the screen was the wrong way round for the viewing angles. Also, there are black borders arou...
by rpdom
Tue Apr 24, 2018 12:09 pm
Forum: Advanced users
Topic: How to expand Virtual Memory on RPi B3 +?
Replies: 24
Views: 457

Re: How to expand Virtual Memory on RPi B3 +?

WHY NOT, THE SPACE IS THERE! If you are needing to use virtual memory (swap space) on a Pi (or almost any other server really), you need to reconsider things. Are you using the right hardware? Is your application being too memory hungry? Using virtual memory on a Pi is even worse than using it on a...
by rpdom
Tue Apr 24, 2018 10:01 am
Forum: General discussion
Topic: Is there a way to have a single button initiate a call to play a prerecorded message.
Replies: 4
Views: 103

Re: Is there a way to have a single button initiate a call to play a prerecorded message.

I'm not sure it would be quite as simple as people are implying to script it to use SIP (as the OP requested). It is possible though.
by rpdom
Tue Apr 24, 2018 4:39 am
Forum: General programming discussion
Topic: SMI Documentation ?
Replies: 17
Views: 3885

Re: SMI Documentation ?

Some details are given the the BCM2835-ARM-Peripherals file (here). I think it was on page 102 or near there that most of the GPIO alternative pin mappings are listed. ALT1 on most pins is for SMI. The https://pinout.xyz site also shows them, but you have to check each pin to find its SMI function.
by rpdom
Tue Apr 24, 2018 4:25 am
Forum: General discussion
Topic: SenseHat Callibration for Compass
Replies: 11
Views: 288

Re: SenseHat Callibration for Compass

Yes I have done sudo apt-get update and upgrade and after attempting to install I got the same error message. I even wiped and restarted the sd and then followed the same steps after updating to no avail. Aha! Please do sudo apt-get update again. Then try the install. On a recent upgrade the packag...
by rpdom
Mon Apr 23, 2018 7:44 pm
Forum: Advanced users
Topic: How to expand Virtual Memory on RPi B3 +?
Replies: 24
Views: 457

Re: How to expand Virtual Memory on RPi B3 +?

That is up to the RPF to make that decision. Their decision is right now to keep that compatability since one of their goals is to provide an affordible computer to teach stidents worldwide including third world countries where even a $35.00 is an expensive purchase for many. It is nothing to do wi...
by rpdom
Mon Apr 23, 2018 7:09 pm
Forum: General discussion
Topic: Controlling three solenoid valves with 12 mA limit
Replies: 18
Views: 458

Re: Controlling three solenoid valves with 12 mA limit

From the Fairchild Semi datasheet
30N06L.png
30N06L.png (15.62 KiB) Viewed 194 times
by rpdom
Mon Apr 23, 2018 6:26 pm
Forum: Beginners
Topic: Simple question about updating Raspbian after new version released...
Replies: 5
Views: 136

Re: Simple question about updating Raspbian after new version released...

The main difference between doing an upgrade and installing a new image is that if an extra package has been included in the new image, and isn't referenced by any existing (updated) packages in the old image, then it won't get installed. (For the benefit of the readers, including me) Can you give ...
by rpdom
Mon Apr 23, 2018 5:11 pm
Forum: Beginners
Topic: Simple question about updating Raspbian after new version released...
Replies: 5
Views: 136

Re: Simple question about updating Raspbian after new version released...

Hi guys. i started my journey with linux when Raspbian was released on 2018-03-13. Now we have 2018-04-18 available. My question is... To get all the functionalities from new image do i have to reflash my SD card and configure everything from scratch? To update my Pi i use: sudo apt update sudo apt...
by rpdom
Mon Apr 23, 2018 4:40 pm
Forum: General discussion
Topic: Controlling three solenoid valves with 12 mA limit
Replies: 18
Views: 458

Re: Controlling three solenoid valves with 12 mA limit

the FQP 30N06L turn on voltage (Vgs) is spec'd as 1.0 to 2.4 V to turn on the FET The spec sheet I'm looking at says different. Min 2.0 and max 4.0 for a drain current of only 250 micro-amps. vgs.png There is a difference between the 30N06 and 30N06 L . Lower gate threshold voltage for a start.
by rpdom
Mon Apr 23, 2018 3:59 pm
Forum: Beginners
Topic: Stretch problems
Replies: 8
Views: 264

Re: Stretch problems

The things was that one of the upgrades changed the repositories. It invalidated the old one, so no packages in that repo showed as existing, until the index was rebuilt for the new repository by doing an update.
by rpdom
Sun Apr 22, 2018 9:58 pm
Forum: Interfacing (DSI, CSI, I2C, etc.)
Topic: How much external power from Zero?
Replies: 14
Views: 407

Re: How much external power from Zero?

Few things stand up from "schematic" There are two 3,3V pins on header - nice This is a well known fact. The layout of the 40 pin header is standard across the Raspberry Pi range (other than the early models with 26 pin headers and the CM modules). The "processor" runs on 1.8 V - so how does it man...
by rpdom
Sun Apr 22, 2018 8:42 pm
Forum: Beginners
Topic: Do you browse Facebook on your Pi ?
Replies: 9
Views: 182

Re: Do you browse Facebook on your Pi ?

I'm quite surprised that any of the forum regulars are willing to admit that they even know what faceblob is, much less, that they (some of them) actually use it. Somehow that doesn't surprise me. I mostly to use it to keep in contact with certain members of my family and my large circle of friends...
by rpdom
Sun Apr 22, 2018 4:29 pm
Forum: Beginners
Topic: Do you browse Facebook on your Pi ?
Replies: 9
Views: 182

Re: Do you browse Facebook on your Pi ?

No, I use my fairly hi-end laptop for FB. Sometimes it makes the fan cut in slowly. I wouldn't bother trying it on a Pi, I have more serious things to do with those.
by rpdom
Sun Apr 22, 2018 4:26 pm
Forum: Beginners
Topic: First Pi Project - Multi-Timezone Clock
Replies: 10
Views: 226

Re: First Pi Project - Multi-Timezone Clock

I have the Model B+ That should be capable of providing up to 1200mA total to the USB an GPIO 5V pins combined. I believe the firmware defaults to the 1200mA setting on the USB now. The Pi Zero has no fuses or limits. All the 5V connections are directly connected to each other. The main limit is wh...
by rpdom
Sun Apr 22, 2018 3:06 pm
Forum: Troubleshooting
Topic: Need Help with CUPS Printing
Replies: 20
Views: 398

Re: Need Help with CUPS Printing

The driver for the MFC-J44510DW’s file that was downloaded has a suffix of .deb. So I believe the driver is correct. That only means it is for a Debian style Linux system. It doesn't say which CPU type it is for. Proper .deb packages have something like "armhf", "x86-64" or "all" in the name to sho...
by rpdom
Sun Apr 22, 2018 3:00 pm
Forum: Interfacing (DSI, CSI, I2C, etc.)
Topic: How much external power from Zero?
Replies: 14
Views: 407

Re: How much external power from Zero?

julyjim wrote:
Sun Apr 22, 2018 2:15 pm
All I see next to the power USB is "C2 = 1F 54S" chip
Which model of Raspberry Pi Zero do you have? On a Zero 1.3 (Camera, no WiFi) I can see U3 which is the voltage regulator chip. On a Zero W it isn't labelled, but is about the same place on the board.
by rpdom
Sun Apr 22, 2018 10:52 am
Forum: General discussion
Topic: Older Pi OS
Replies: 3
Views: 162

Re: Older Pi OS

by rpdom
Sun Apr 22, 2018 10:23 am
Forum: Python
Topic: wiringpi
Replies: 2
Views: 73

Re: wiringpi

Try another "sudo apt-get update" before trying the install. There was a change released recently which made it necessary to do that, or many packages would appear to be unavailable for install.

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