commit bd6c7237c5c950e30c1532aba649973d706834ab
Author: Arne van Iterson <arne@arnweb.nl>
Date:   Mon Sep 6 20:43:06 2021 +0200

    Putting this on Gitea so I don't lose it

diff --git a/README.md b/README.md
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+++ b/README.md
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+# TI-84_DFPlayer
+TI-84 Plus with inbuilt MP3 player using an ATtiny85 as a communication bridge.
+
+## Usage
+- Put the `.ino` file on your MCU of choice, I used an ATtiny 85.
+- Connect the DFPlayer to the MCU using the Serial port, use pins 0 (RX) and 1 (TX) on the ATtiny 85
+- Connect the calculator to the MCU using its serial connection, use pins 4 (TIP) and 3  (RING) on the ATtiny 85
+- Power the MCU using an external battery or steal power from the calculators batteries, you will need an external power switch and make a voltage devider
+- Put music on the DFPlayers SD card
+- Put DFPlayer.8xp on your calculator to control the DFPlayer
+- Enjoy!
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diff --git a/TI-84_DFPlayer.ino b/TI-84_DFPlayer.ino
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+++ b/TI-84_DFPlayer.ino
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+#include <DFRobotDFPlayerMini.h>
+#include <SoftwareSerial.h>
+#include "CBL2.h"
+#include "TIVar.h"
+
+CBL2 cbl;
+SoftwareSerial SoftSerial(0, 1); // RX, TX
+DFRobotDFPlayerMini DFPlayer;
+
+#define MAXDATALEN 32
+uint8_t header[16];
+uint8_t data[MAXDATALEN];
+
+int onSendAsCBL2(uint8_t type, enum Endpoint model, int *headerlen, int *datalen, data_callback *data_callback);
+int onGetAsCBL2(uint8_t type, enum Endpoint model, int datalen);
+
+void setup()
+{
+  SoftSerial.begin(9600);
+  DFPlayer.begin(SoftSerial);
+  DFPlayer.play(2);
+
+  cbl.setLines(4, 3);
+  cbl.resetLines();
+  cbl.setupCallbacks(header, data, MAXDATALEN, onGetAsCBL2, onSendAsCBL2);
+}
+
+void loop()
+{
+  int rval;
+  rval = cbl.eventLoopTick();
+  if (rval && rval != ERR_READ_TIMEOUT)
+  {
+    SoftSerial.print("eventLoopTick: error code ");
+    SoftSerial.println(rval);
+  }
+}
+
+void sendtoDFP(short command, short parameter)
+{
+  switch (command)
+  {
+    case 1:
+      DFPlayer.next(); break;
+
+    case 2:
+      DFPlayer.previous(); break;
+
+    case 3:
+      DFPlayer.play(parameter); break;
+
+    case 4:
+      DFPlayer.volumeUp(); break;
+
+    case 5:
+      DFPlayer.volumeDown(); break;
+
+    case 6:
+      DFPlayer.volume(parameter); break;
+
+    case 8:
+      DFPlayer.randomAll(); break;
+
+    case 13:
+      DFPlayer.start(); break;
+
+    case 14:
+      DFPlayer.pause(); break;
+
+    case 17:
+      DFPlayer.stop(); break;
+  }
+}
+
+int onGetAsCBL2(uint8_t type, enum Endpoint model, int datalen)
+{
+  uint16_t list_len = TIVar::sizeWordToInt(&(data[0])); // Convert 2-byte size word to int
+  int size_of_real = TIVar::sizeOfReal(model);
+
+  short cmd = TIVar::realToLong8x(&data[size_of_real * 0 + 2], model); // First list element starts after 2-byte size word
+  short parameter = TIVar::realToLong8x(&data[size_of_real * 1 + 2], model);
+
+  sendtoDFP(cmd, parameter);
+
+  return 0;
+}
+
+int onSendAsCBL2(uint8_t type, enum Endpoint model, int *headerlen, int *datalen, data_callback *data_callback)
+{
+  return 0;
+}
diff --git a/TI/DFPlayer.8xp b/TI/DFPlayer.8xp
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Binary files /dev/null and b/TI/DFPlayer.8xp differ
diff --git a/TI/DFPlayer.txt b/TI/DFPlayer.txt
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+0→N
+0→L
+
+Lbl MM
+WisHome
+Menu("DFPlayer Mini","Play",PL,"Pause",PA,"Playback",PB,"Volume",V,"Quit",Q)
+
+Lbl PL
+Send({13})
+Goto MM
+
+Lbl PA
+Send({14})
+Goto MM
+
+Lbl PB
+WisHome
+Menu("Playback","Next",NE,"Previous",PR,"Stop",ST,"Shuffle",SH,"Select",SE,"Back",MM)
+
+Lbl NE
+Send({1})
+Goto PB
+
+Lbl PR
+Send({2})
+Goto PB
+
+Lbl ST
+Send({17})
+Goto PB
+
+Lbl SH
+Send({8})
+Goto PB
+
+Lbl SE
+Input "Select song:    ",N
+Send({3,N})
+Goto PB
+
+
+Lbl V
+WisHome
+Menu("Volume","Volume Up",VU,"Volume Down",VD,"Set",VS,"Back",MM)
+
+Lbl VU
+Send({4})
+Goto V
+
+Lbl VD
+Send({5})
+Goto V
+
+Lbl VS
+Input "Set volume  1-30: ",L
+Send({6,L})
+Goto V
+
+Lbl Q
+Stop
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