X API update

Attempts to use the X API (formerly Twitter) for projects with Max/MSP have been disappointing at best. Most of the API is behind a paywall now.  The cost is $5000 per month. to implement streaming API used in projects like this:  https://reactivemusic.net/?p=5786

The free tier only allows basic tweeting and user lookup. Search is not available.

I was able to find only one node example that actually worked in the free tier. By “Coding with Ado”. The code requests a token from X, and then you enter a timestamped pin number to continue. Making it worthless for programs and bots. https://youtu.be/G5ZW5j5cwHk?si=vbAtGa0bQ3T_tga9

A local copy of the source code for this is in tkzic/nodetweet3/index.js

Other options

Another option with X, is to use a service like Socialdata. https://socialdata.tools/

There service sits in the middle to handle X API calls. You are charged by the number of calls. It doesn’t offer streaming either, but you can simulate it by calling a search every few seconds.

Other social media options

There are API’s for other social sites like facebook, instagram, tiktok, etc.,

MBTA Boston train map

This post describes an update of a previous version. The old version can be found here: https://reactivemusic.net/?p=20329

Moving markers

In the previous version, all of the markers for each train line were deleted and redrawn in a group at the polling interval. In this version the train markers move to their new location when the data is polled.

The map is drawn using Leaflet. The moving marker library is from Ivan Sanchez https://www.npmjs.com/package/leaflet.marker.slideto

The project uses the MBTA JSON API, to query vehicle data for each train line. the geo coordinates of the trains are sent via websockets to the client map page.

This project is a work in progress and not available yet.

Files:

node server: internetsensors/mbtanode2/index.html

html map client: internetsensors/mbtanode2/mbtatrain2.html

Instructions

// to run, type node index.js at a command line.
// then open a web browser to: http://127.0.0.1:8124/
// type 'go' into the text box below the map, and press 'send' button
// in a few seconds the train markers will magically appear

Max/MSP text to Morse code generator

work in progress. not published.

I needed a text to morse code generator in Max for the Twitter streaming map project. There was an ancient one that used [mxj] but its kind of a pain to use that object. I thought it can’t be that difficult to write one? I didn’t really have any idea where to start. Something about the blank Max patch causes brain activity? I went through about 5 different approaches. Eventually came up with this pattern thing, from thinking about the lighted buttons on the tr-808 drum machine.

For example, the letter A is . _ (dot dash)

morse code has rules for spacing:

dot = 1
space between tones = 1
dash = 3
space between letters = 3
space between words = 7

If you think of a drum machine pattern, the pattern for letter A would be: 1 0 1 1 1 0 0 0  (with the 3 trailing 0’s for letter spacing)

I made a [coll] with all the letter patterns indexed by ascii codes.

Then just concatenate letter patterns, for a given block of text,  together into one big list and run it through [zl.nth] clocked by a [metro] and [counter]. the ones and zero’s turn an oscillator on and off.

local file: tkzic/internetsensors/twitter-stream2/morse5.maxpat

Milford Graves Experiment

Milford Graves was one of my all time favorite musicians. His approach to percussion, and music generally, was unique in a way that defies explanation.

I sampled a bunch of clips of his drumming into Ableton live and then experimented with the Buffer Shuffler 2.0 device to see if I could randomize small slices, ie., several seconds each, of longer samples – without losing the “texture” of the original recordings.

Here is an example of what it sounds like:

This video shows a clip from David Murray’s “Real Deal” running through Buffer Shuffler using slices only about 2-3 seconds in length. The slicing rate is just arbitrary, since there is no warping or specific clock pulse.

Local files: tkzic/aardvark/milfordgraves1 project/milfordgraves1a.als

Hamlib C programming example on Mac OS

Hamlib provides a standardized computer interface for amateur radios.

I was able to get it to run in a C program on Mac OS Ventura.

Instructions

Install Hamlib using homebrew. ie,., brew install hamlib.

Download this sample C test code – testrig.c – from https://hamlib.sourceforge.net/manuals/1.2.15/_2tests_2testrig_8c-example.html or https://github.com/Hamlib/Hamlib/blob/master/tests/testrig.c

Change the SERIAL_PORT constant to the actual port name. Change the baud rate.

Lookup the hamlib code for your radio. https://github.com/Hamlib/Hamlib/wiki/Supported-Radios

For example, for the Elecraft K3, the code is 2043.

compile using this command:

gcc testrig.c -I /opt/homebrew/include -L /opt/homebrew/lib -l hamlib -o testrig

Type this to run the program:

./testrig 2043

Assuming 2043 is the rig number. If all is working, the program will set a bunch of stuff on your radio, changing frequency, mode, etc.,

Local files: tkzic/chatgpt/radio/ctest.c

notes: link to instructions for compiling hamlib manually: https://github.com/Hamlib/Hamlib/blob/master/README.osx

Using Web Serial API for Radio CAT interface

Work in progress…

An html example that sends and receives CAT commands with an Elecraft K4 connected to the serial port of the machine running the web browser.

The file was built using examples from this article by Francois Beaufort. https://developer.chrome.com/docs/capabilities/serial It’s an excellent resource for Web Serial.

The html file for this project is here: http://www.pr0jex.com/serial/index.html

But it won’t run from that server. It only runs locally.

Instructions

Download the index.html file from the link above. start a local web server, eg., “npx http-server” and enter the server address into a Chrome browser.

When you press connect, the browser will prompt you to select a serial port for the radio.  On my computer the K4 serial ports appear something like: cu2.usbserial-21100. There are 2 ports. Select either one.

Then press read. If you spin the dial on the K4, and it is autoinfo mode, you should see CAT commands in the read window.

enter a CAT command in the write window and press the write button. It is preloaded with “fa7;” which sets frequency to 7 MHz.

Press the disconnect button to end your session.

local files tkzic/webusb/serial2/index.html

 

Virtual serial port pairs in Mac OSx

I was unable to find any apps to create virtual serial ports for later versions of Mac OSx eg., Catalina.

There is a partial solution using the linux socat utility. It will create functioning vsp’s but the ports will not be detected by most apps, like Max/MSP.  I tried setting a symlink to files in /dev using tty. and cu. prefixes. eg., /dev/tty.x1. But apps that look for serial ports still couldn’t detect the vsp’s.

Instructions

  1. download and install socat using macports or brew. eg., “sudo port install socat”
  2. Disable SIP (system integrity protection). In Catalina, reboot holding cmd+r. Then type: “csrutil disable” into a terminal window. Reboot – Note: you probably don’t need to do this if you aren’t setting up a link in /dev – which so far doesn’t work anyway
  3. Run one of the following commands:

socat -d -d pty,raw,echo=0 pty,raw,echo=0

sudo socat -d -d pty,link=/dev/tty.x0,raw,echo=0,user=tkzic,group=staff pty,link=/dev/tty.x1,raw,echo=0,user=tkzic,group=staff

What works and what doesn’t

After setting up the ports, you can send data in one port and out the other, for example, type the following into 2 different terminal windows.

cat /dev/ttys004

echo “Hello World” > /dev/cu.x1

This works great. But, so far, using sym links – the ports don’t show up in any app that accesses serial ports. Still working on this…

Using socat you can also setup a serial/tcp pair – this may be a solution for some projects.

2021 WPX CW – TF/KA1IS

Amatuer radio station TF/KA1IS in Akureyri, Iceland – May 2021.

It is 1:52 AM: Sunset/Sunrise over Eyjafjörður.

  • Category: Single Operator, All Band, low power.
  • Claimed score: QSO’s: 882 Prefixes = 499 Total Score = 1,033,928 (34 hours).

Station:

  • Elecraft KX2
  • Elecraft KXPA100
  • 5 meter whip antenna with 4 elevated radials and loading coil for 40/80 meter bands

New SC playlists – piano music 2

Demo tracks are now available in these Soundcloud playlists for an upcoming recording project. The letter ‘c’ following a track name indicates the chart has been completed.