commit 98cf0a42d2614dd2726542e8ce941e94a894a18e
Author: n loewen <nick@nloewen.com>
Date:   Wed Aug 9 18:06:34 2023 +0100

    Initial commit

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+.vscode
+.DS_Store
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diff --git a/example--fill-display-program.txt b/example--fill-display-program.txt
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+0000001111111110000001010000000100000101000000010000010100000001000001110000000100000111000000010000001100000001000000010000000000000011111111100000011000000000000001100000000000000110000000000000100000000000000010000000000000000000000000000000000000000000
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diff --git a/readme.md b/readme.md
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+# Create square wave patterns from binary strings
+
+This script turns a binary string into a square-wave pattern.
+
+It is intended for creating embroidery patterns based on programs for my paper computer.
+
+The output is formatted as if the data is being sent over an 8-bit data bus — see the [reference image below](#format-reference-image).
+
+## Use
+
+```
+./square-wave-from-binary.js bin.txt
+```
+
+The input must be a text file containing nothing but 0s and 1s (no spaces, newlines, etc). It must be an even number of 8-bit bytes in length.
+
+## Example output
+
+```
+01234567  01234567  01234567  01234567
+▄▀▄▄▄▄▄▄  ▄▄▄▄▄▄▄▄  ▄▀▄▄▄▄▄▄  ▄▄▄▄▄▄▄▄
+
+▄▀▄▄▄▄▄▄  ▄▄▄▄▄▄▄▄  ▄▀▄▄▄▄▄▄  ▄▄▄▄▄▄▄▄
+
+▄▀▄▄▄▄▄▄  ▄▄▄▄▄▄▄▄  ▄▀▄▄▄▄▄▄  ▄▄▄▄▄▄▄▄
+
+▄▀▄▄▄▄▄▄  ▄▄▄▄▄▄▄▄  ▄▀▄▄▄▄▄▄  ▄▄▄▄▄▄▄▄
+
+▄▀▄▄▄▄▄▄  ▄▄▄▄▄▄▄▄  ▄▀▄▄▄▄▄▄  ▀▄▀▄▄▄▄▄
+
+▄▀▀▄▀▄▀▄  ▀▄▀▄▄▄▄▄  ▄▀▀▄▀▄▀▄  ▄▄▄▄▄▄▄▄
+
+▀▀▄▄▄▄▄▄  ▀▄▀▄▀▄▄▄  ▀▀▀▄▀▄▀▄  ▄▄▄▄▄▄▄▄
+
+▀▄▀▀▀▀▀▀  ▀▀▀▀▀▀▀▄  ▀▄▄▄▄▄▄▄  ▄▄▄▄▄▄▄▄
+
+01234567  01234567  01234567  01234567
+```
+
+## Format reference image
+
+![](https://www.nutsvolts.com/uploads/wygwam/NV_1007_Martin_Figure09.jpg)
+
+(From [Nuts and Volts](https://www.nutsvolts.com/uploads/wygwam/NV_1007_Martin_Figure09.jpg).)
diff --git a/square-wave-from-binary.js b/square-wave-from-binary.js
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+#!/usr/bin/env node
+
+// Input file must contain a binary string with no spaces, linebreaks, etc.
+
+const fs = require('fs');
+const filename = process.argv[2];
+const inputFile_str = fs.readFileSync(filename, 'utf8');
+
+const create_square_wave_string = (s) => {
+  s = s.replace(/1/g, '▀');
+  return s = s.replace(/0/g, '▄');
+}
+
+const number_hex_string = (quantity) => {
+  let output = '';
+  let current_digit = 0;
+  for (let i = 0; i < quantity; i++) {
+    current_digit = i % 8;
+    output = output + current_digit;
+  }
+  return output;
+}
+
+const binary_string_to_bus_strings = (input) => {
+  let output = ['','','','','','','',''];
+  let input_bytes = input.match(/.{1,8}/g);
+
+  input_bytes.forEach( (byte) => {
+    let byte_array = byte.split('');
+    for (let i = 0; i < 8; i++) {
+      output[i] = output[i] + byte_array[i];
+    }
+  });
+
+
+  // Print output
+  let nums = number_hex_string(output[0].length);
+  let spaced_nums = nums.match(/.{1,8}/g).join('  ');
+  console.log();
+  console.log(spaced_nums);
+
+  output.forEach( (s) => {
+    let spaced = s.match(/.{1,8}/g).join('  ');
+    console.log(create_square_wave_string(spaced));
+    console.log();
+  });
+  console.log(spaced_nums);
+  console.log();
+}
+
+binary_string_to_bus_strings(inputFile_str);
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