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Hindsight and brain farts

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Caverns of Zork - retro electronic music(ish)

Caverns of Zork - retro electronic music(ish)

Electronic music is a long standing interest that dates back to my 1970s Popular Electronic subscription.  Recently I was searching the Buffalo Library's database for the next episodes of Game of Thrones when I decided to search for electronic music.  One CD caught my eye with recordings from 9 BA(Before Atari). The list of LPs was much more extensive. That lead to the retrieval of my turn table from a friend, who was going to digitize his collection of LPs for the last 5 years.  I have bee

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A8 MMS Sn - changing presets

A8 MMS Sn - changing presets

Changing presets/patches/voices/instruments/programs on your MIDI gear was rather easy in the early 80's. Having more the 128 instruments on a digital synth was unbelievable.  So unbelievable that the original MIDI standard got a special command number( 192+channel #-1 ) and a 7bit number (0  - 127) to made the change.    The MIDI Music System software provided the command Sn to accomplish this. Insert Sn  between two notes in a voice and the patch magically changes.   Then

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A8 MMS programing drum tracks

A8 MMS programing drum tracks

I never really thought about it but a drummer has 2 hands and 2 feet; that's 4 percussion instruments that can be struck at the same time.  But are they really?   I'm no drummer so the best place to start programming drum patterns was using a book of drum patterns. I chose to start with 200 Drum Patterns by Rene-Pierre Bardet and a chart of the standard MIDI note number for the percussion instruments.   MIDI Music System was loaded up and a drum pattern was entered. Two or th

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A8 MMS Voice File Data Explanation

A8 MMS Voice File Data Explanation

Using MIDI MUSIC SYSTEM software to build music compositions seems to fit my skill set.  I'm not proficient at reading music but I can translate it.  My latest arrangement was a Celtic folk song for flute and drums.  Music was entered into MMS and a simple drum pattern was added.  It sounded terrible. Turns out that a synthesized flute doesn't need to breath and sounds very mechanical without those breaks.   Selected notes were shortened and rests were inserted to maintain timing and g

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Easy Atari Page Flipping - a tutorial

If you typed in your first BASIC "HELLO" program and  made some small modification then there's a chance you've been typing ever since.  I've had some time on my hands and read an old tutorial that begged to be inputted and modified.   COMPUTE! September 1983 contains the article  "Easy Atari Page Flipping" by Chris Allen.  It's  a program to demonstrate page flipping on the Atari with plenty of room for experimentation.   https://www.atarimagazines.com/compute/issue40/page_f

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Digitizing 8-bit sound with the PO-33 K.O!

Digitizing 8-bit sound with the PO-33 K.O!

Teenage Engineering's PO-33 K.O! is an 8bit sampler.  If you don't own an 8-bit computer, this statement might seem a bit restrictive but it can handle sampling much more then just 8 bit sound sources.    A YouTube search of "PO-33 KO" can provide a plethora of videos on the subject.       I've had mine for a few months and am just now finding the free time to play with it.  The video is a first attempt at a loop using samples from the Atari 130XE.  The MP3 is the s

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Atari Monotone Synth -  software for AU2PORTA

Atari Monotone Synth - software for AU2PORTA

There were several issues left unresolved while programing the MIDI IN  interface for the ATARI8 joystick ports.  The first was to revert back to using the Cassette Motor Control pin on the SIO port for data flow control.  This was accomplished with the AU2PORTA shield design.     The second consideration was the startup default joystick pin status.  The joystick pins are set to high on startup and then grounded to zero by the joystick switches.  There is some reverse logic

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XBOX Controller With CX40 Cord mod

XBOX Controller With CX40 Cord mod

There I was, in garage sale heaven. Standing over a box of second hand XBOX controllers.  I got a little less excited when I noted how second hand they were. I thought I would salvage parts and asked, "How much?".  She said, "$2". I said, "OK."  He looked like he just lost an old friend and his wife was telling herself, "I should have said 3!"   Fast forward 16 months and I'm sorting them into a box labeled "electronic recycle" because I was to lazy to open them up for salvage.  One di

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Ping)) / AU2PORTA Controls Atari pitch

Ping)) / AU2PORTA Controls Atari pitch

Back in January of 2015, I wanted of use a PING)) ultrasonic sensor to measure distance and send it to the Atari using the 850 - RS232 ports.  I initially thought that  I could move my hand in front of the sensor and the resulting change in desistance could be used to change the frequency of the sound command.  This might have worked if the SIO port could be used to make sound .AND. transmit data to the 850 interface at the same time. It doesn't. So, I forgot about the sound and just got the dis

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Arduino Shield For PORTA Input

Arduino Shield For PORTA Input

Over the years I've been using an Arduino UNO to setup data for transfer to the Atari Joystick ports.  The first attempt was to read the data from a  Wii nunchuk and translate it to joystick movements.  Lately I've been experimenting reading midi data using an Arduino Midi Shield, along with using the Cassette Motor Control pin on the SIO port as feedback to the Arduino. You may have read some of these blogs.   During the "Switched On POKEY" music experiments, there were many modificat

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A Sound Understanding

I have spent a little time looking through some ATARI Assembly Language books for sound routines that I might find useful. I found several examples in ATARI Assembly Language Programmer's Guide by Allan Moose and Marian Lorenz. Chapter 5, appropriately titled "Sound", has 3 programs that I wanted to hear. BOX 31 - Envelope, BOX 32 - Tremolo, and BOX 33 - Vibrato. These are BASIC examples using USR routines. The ml programs were listed in BOX31A, BOX32A, and BOX33A. The first program was

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Finally, I'm Playing MIDI Notes using MAC/65 Assembler Code

Do you remember me mentioning that the first attempt to write a machine language program to read MIDI data delivered to the Atari joystick port was a complete failure? The Arduino hardware has remained the same. The joystick trigger and cassette motor control(CMC) pin on the SIO port are still being used to control data flow. But this time I redefined the project specs to simplify the ML program and tested the ML data transfer routine as a USR call. The USR routine was written to replace th

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SAM sings a round

There was a Korg microKorg under the Christmas tree last year; only because my wife wouldn't let me set it up in November when it was purchased. I did manage to get the manual out of the box before it was wrapped. So for a whole month I read the manual and watched youTube videos.   The microKorg has a vocoder. This suggested that the audio output from an Atari running SAM could be hooked up to the line-in on the Korg. Then the Korg could modifiy, modulate, or magically manipulate the signa

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A journey to Bach's Invention 1 and other miscellaneous updates

After recording PRELUDE1.MP3 it seemed that the Atari BASIC sound program needed to be reprogrammed in assembly. I got out the MAC65 cart and two days later things were so messed up I wasn't sure if it was the Arduino and/or Atari software or the Arduino interface hardware giving me the headaches.   I decided to go back and setup the equipment/software as it was for "house of the Rising sun". That seemed to work fine and it still did.   I couldn't just turn it off and start programming.

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AMS v1.0 Command Summary and Stereo Recording

I've started a project to recreate W. Carlos's Switched on Bach album playlist using the Atari8 as a sound source. A goal on my bucket list is to finish it. I intend to use the MIDI Music System to send data to other Ataris that will act as sound synthesizers. My original thought was to have the ability to play the songs in real time; something Carlos couldn't do in 1968 when the album was published. Then I thought of something else that lead me to something else until I asked, "Am I ever

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MIDIPLUS miniEngine USB - first impressions

I ordered the MIDIPLUS miniEngine USB sound synthesizer to reward myself for doing something special. This is the first chance I've had to play with it and can't remember exactly what that something was. Maybe it wasn't that special.   The thing that interested me most about this general midi sound module is its size( 3" X 4" X 1"). I just don't have the room to keep the TG-33 and sound mixer on my desk. If I want to have a short retro session, it can quickly be set up in a few minuet

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DB9 Experimenter Box

Someday I'm going to take a photo while experimenting with DB9 connectors on the Atari Joystick ports or RS-232 ports and this box is going to be in the middle of a mess of wires. Some one is likely to ask, "What's up with that box?" This is an attempt to have this information ready to answer that very question.         If your from the future, I guess it worked.       It is simply a pass through box for each of the pins of a DB9 connector. It simply passes the signal for a pin to p

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Metronome - Software Timer Demo in DE RE Atari

I was thinking about making an 8-step sequencer for a Gakken SX-150 Mark II analog synthesizer using the Atari8. Then I thought, "Why not just use the Pokey chip instead of the Gakken? " Then I thought, "Why not develop it using Diamond GOS? I'll bet no one has done that yet." While reading up on the hardware and software timers, the metronome program in De Re Atari looked like it could be easily modified with a Diamond upgrade to change the tempo using a slide bar. It was a good idea but

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Kaleid-a-vision: A Music Visualizer Technique for Retro Computers

I can't say I did this on my Atari8, but I can truthfully say I did it with my Atari8. This video was recorded using the Kaleid-a-vision hardware, Atari8 and video camera. I would suppose any retro computer or video game machine could be used as a video source. The Atari was running a GR9 Demo program. The one with the rotating coins and then vertical color bars bouncing from the top to the bottom of the screen. The music is from some music I built using a Garage Band demo version

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DH100 - A POKEY House of the Rising Sun

I finally put together a semi-live performance using the DH-100 Digital Horn to control the sound of an Atari XE computer. I know that improvements to the hardware/software is not going to improve my ability to play the horn but there is much that can be done to improve the sound. There were some changes made to the last Atari program. First, the second hi-res voice was added and an off-set. This was to see how much of an effect the phase shift would have on the combined frequencies. In pl

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Nunchuk Your Way To a Better Pac-man Score

While playing Pac-man with a standard Atari Joystick, how often have you missed a turn? I may have a solution, if its due to pushing the joystick to far off the four directional axis. If its due to a slow reaction time then you're still on your own.   I noted while playing Pac-man that my granddaughter would rotate the joystick base and start pushing the joystick into the diagonal directions(and so was I to a lesser extent). When 2 directional buttons on the joystick are pressed Pac-man determ

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DH-100 - The Sound of Possible Music

Finally got the DH-100 digital horn telling the Atari8 what tones to make and when. There was a couple of times I didn't think it was going to happen. Luckily the compiled basic program runs fast enough to keep up with the filtered data from the Arduino. Some sound tests have been recorded and placed in the following ZIP file. sound checks.zip Nothing has been done to enhance the sound from the Pokey chip other then combining 2 channels to allow the use of 16 bits to define the tones.

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DH100 - Interface program / A8 - Frequency tables

I finished work on the last blog entry, unplugged the keyboard and plugged the digital horn. I was a little surprised to see how much data the breath pressure sensor(after touch) was being streamed to the Atari 8. Far more then it could keep up with. The Arduino needed to be reprogramed to reduce the number of bytes being send to the Atari8. The interface software was tested with the previous Atari 8 test program and it performed much better. The data seemed to make sense and it was diffic

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DH100 - MIDI Communication established

I was going to start writing my list of resolutions for 2018. Then I thought about writing about what I didn't accomplish in 2017. Then I decided to just work on programing the interface and get the Atari to read and print the MIDI data stream through the joystick port. I had high hopes of creating a midi monitor that would accept the data and print out the commands as they were received but all that extra code was getting in the way of finding errors. I was happy when I got the Atari8 and Ar

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