From 961d4ac5f598eb73af4bd26e24129717fcf50396 Mon Sep 17 00:00:00 2001
From: Kosma Moczek <kosma@kosma.pl>
Date: Fri, 25 Nov 2022 13:57:00 +0100
Subject: [PATCH] initial commit

---
 README.md        |  41 +++++++
 VF60-ESP8266.ino | 292 +++++++++++++++++++++++++++++++++++++++++++++++
 2 files changed, 333 insertions(+)
 create mode 100644 README.md
 create mode 100644 VF60-ESP8266.ino

diff --git a/README.md b/README.md
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index 0000000..98e1f4a
--- /dev/null
+++ b/README.md
@@ -0,0 +1,41 @@
+# VF60 WiFi Driver
+
+Minimalistic WiFi driver software for VF60.
+
+## Connection
+
+Use the RS-232 port, as documented [here](https://github.com/ggajoch/vf60-vfd-display).
+Note that the connector on the display is RS232 voltage levels - to connect an ESP8266
+you have two options:
+
+1. Use a level shifter like MAX3232.
+2. Disassemble the display and remove the internal level shifter,
+   then connect the ESP8266 directly to the level shifter pads
+   on the PCB.
+
+## Configuration
+
+Change the SSID and password at the beginning of the file. Flash using Arduino IDE.
+
+## Usage
+
+* `http://<display IP>/display?line1=...&line2=...` - sets display content
+* `http://<display IP>/brightness?brightness=0..5` - sets display brightness
+
+## Language support
+
+On the HTTP side, use UTF-8.
+
+On the display side, the text is converted to CP-852 (Polish codepage)
+as that's the author's native language. To add support for more languages:
+
+1. Add and use a function like `UTF8toCP852()` but supporting a different codepage.
+2. Add and use a function line `codepage_852()` but switching the display to a different codepage.
+   To find the correct invocation, use trial and error, trying different values instead of `\x07`.
+
+Pull requests are welcome to add more language support; I won't do it because I'm lazy.
+
+## TODO
+
+- Show the display's IP address upon startup.
+- Add more languages.
diff --git a/VF60-ESP8266.ino b/VF60-ESP8266.ino
new file mode 100644
index 0000000..eaa83e7
--- /dev/null
+++ b/VF60-ESP8266.ino
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+/*
+ * VF60 ESP8266 WiFi Driver
+ */
+
+#include <ESP8266WiFi.h>
+#include <WiFiClient.h>
+#include <ESP8266WebServer.h>
+
+const char* ssid     = "Internet of Shit";
+const char* password = "The S in IoT stands for Security";
+
+
+// NOTE: The value is not a Unicode codepoint but a byte sequence.
+// Generated using https://www.acc.umu.se/~saasha/charsets/?charset=cp852&charset=cp852
+unsigned char UTF8toCP852(uint32_t value)
+{
+  switch (value) {
+    case 0xc387: return 0x80;
+    case 0xc3bc: return 0x81;
+    case 0xc3a9: return 0x82;
+    case 0xc3a2: return 0x83;
+    case 0xc3a4: return 0x84;
+    case 0xc5af: return 0x85;
+    case 0xc487: return 0x86;
+    case 0xc3a7: return 0x87;
+    case 0xc582: return 0x88;
+    case 0xc3ab: return 0x89;
+    case 0xc590: return 0x8a;
+    case 0xc591: return 0x8b;
+    case 0xc3ae: return 0x8c;
+    case 0xc5b9: return 0x8d;
+    case 0xc384: return 0x8e;
+    case 0xc486: return 0x8f;
+    case 0xc389: return 0x90;
+    case 0xc4b9: return 0x91;
+    case 0xc4ba: return 0x92;
+    case 0xc3b4: return 0x93;
+    case 0xc3b6: return 0x94;
+    case 0xc4bd: return 0x95;
+    case 0xc4be: return 0x96;
+    case 0xc59a: return 0x97;
+    case 0xc59b: return 0x98;
+    case 0xc396: return 0x99;
+    case 0xc39c: return 0x9a;
+    case 0xc5a4: return 0x9b;
+    case 0xc5a5: return 0x9c;
+    case 0xc581: return 0x9d;
+    case 0xc397: return 0x9e;
+    case 0xc48d: return 0x9f;
+    case 0xc3a1: return 0xa0;
+    case 0xc3ad: return 0xa1;
+    case 0xc3b3: return 0xa2;
+    case 0xc3ba: return 0xa3;
+    case 0xc484: return 0xa4;
+    case 0xc485: return 0xa5;
+    case 0xc5bd: return 0xa6;
+    case 0xc5be: return 0xa7;
+    case 0xc498: return 0xa8;
+    case 0xc499: return 0xa9;
+    case 0xc2ac: return 0xaa;
+    case 0xc5ba: return 0xab;
+    case 0xc48c: return 0xac;
+    case 0xc59f: return 0xad;
+    case 0xc2ab: return 0xae;
+    case 0xc2bb: return 0xaf;
+    case 0xe29691: return 0xb0;
+    case 0xe29692: return 0xb1;
+    case 0xe29693: return 0xb2;
+    case 0xe29482: return 0xb3;
+    case 0xe294a4: return 0xb4;
+    case 0xc381: return 0xb5;
+    case 0xc382: return 0xb6;
+    case 0xc49a: return 0xb7;
+    case 0xc59e: return 0xb8;
+    case 0xe295a3: return 0xb9;
+    case 0xe29591: return 0xba;
+    case 0xe29597: return 0xbb;
+    case 0xe2959d: return 0xbc;
+    case 0xc5bb: return 0xbd;
+    case 0xc5bc: return 0xbe;
+    case 0xe29490: return 0xbf;
+    case 0xe29494: return 0xc0;
+    case 0xe294b4: return 0xc1;
+    case 0xe294ac: return 0xc2;
+    case 0xe2949c: return 0xc3;
+    case 0xe29480: return 0xc4;
+    case 0xe294bc: return 0xc5;
+    case 0xc482: return 0xc6;
+    case 0xc483: return 0xc7;
+    case 0xe2959a: return 0xc8;
+    case 0xe29594: return 0xc9;
+    case 0xe295a9: return 0xca;
+    case 0xe295a6: return 0xcb;
+    case 0xe295a0: return 0xcc;
+    case 0xe29590: return 0xcd;
+    case 0xe295ac: return 0xce;
+    case 0xc2a4: return 0xcf;
+    case 0xc491: return 0xd0;
+    case 0xc490: return 0xd1;
+    case 0xc48e: return 0xd2;
+    case 0xc38b: return 0xd3;
+    case 0xc48f: return 0xd4;
+    case 0xc587: return 0xd5;
+    case 0xc38d: return 0xd6;
+    case 0xc38e: return 0xd7;
+    case 0xc49b: return 0xd8;
+    case 0xe29498: return 0xd9;
+    case 0xe2948c: return 0xda;
+    case 0xe29688: return 0xdb;
+    case 0xe29684: return 0xdc;
+    case 0xc5a2: return 0xdd;
+    case 0xc5ae: return 0xde;
+    case 0xe29680: return 0xdf;
+    case 0xc393: return 0xe0;
+    case 0xc39f: return 0xe1;
+    case 0xc394: return 0xe2;
+    case 0xc583: return 0xe3;
+    case 0xc584: return 0xe4;
+    case 0xc588: return 0xe5;
+    case 0xc5a0: return 0xe6;
+    case 0xc5a1: return 0xe7;
+    case 0xc594: return 0xe8;
+    case 0xc39a: return 0xe9;
+    case 0xc595: return 0xea;
+    case 0xc5b0: return 0xeb;
+    case 0xc3bd: return 0xec;
+    case 0xc39d: return 0xed;
+    case 0xc5a3: return 0xee;
+    case 0xc2b4: return 0xef;
+    case 0xc2ad: return 0xf0;
+    case 0xcb9d: return 0xf1;
+    case 0xcb9b: return 0xf2;
+    case 0xcb87: return 0xf3;
+    case 0xcb98: return 0xf4;
+    case 0xc2a7: return 0xf5;
+    case 0xc3b7: return 0xf6;
+    case 0xc2b8: return 0xf7;
+    case 0xc2b0: return 0xf8;
+    case 0xc2a8: return 0xf9;
+    case 0xcb99: return 0xfa;
+    case 0xc5b1: return 0xfb;
+    case 0xc598: return 0xfc;
+    case 0xc599: return 0xfd;
+    case 0xe296a0: return 0xfe;
+    case 0xc2a0: return 0xff;
+    default: return '?';
+  }
+}
+
+// Naive UTF8 parser based on: https://www.omarpolo.com/post/parsing-utf8.html
+String UTF8toCP852(String s)
+{
+  unsigned char result[20+1];
+  size_t len = 0;
+
+  for (int i=0; i<s.length() && len<20; i++) {
+    unsigned char c = s[i];
+    // Is it ASCII?
+    if ((c & 0x80) == 0) {
+      result[len++] = c;
+      continue;
+    }
+    // okay, it's a multibyte sequence
+    uint32_t value;
+    if ((c & 0xE0) == 0xC0) {
+      // 2-byte sequence
+      value = (s[i] << 8) | (s[i+1]);
+      i += 1;
+    } else if ((c & 0xF0) == 0xE0) {
+      // 3-byte sequence
+      value = (s[i] << 16) | (s[i+1] << 8) | (s[i+2]);
+      i += 2;
+    } else if ((c & 0xF8) == 0xF0) {
+      // 4-byte sequence
+      value = (s[i] << 24) | (s[i+1] << 16) | (s[i+2] << 8) | (s[i+3]);
+      i += 3;
+    } else {
+      // this is not a UTF8 string :(
+      value = 0xFFFFFFFF;
+    }
+    // convert the sequence of UTF8 bytes into a CP852 value
+    result[len++] = UTF8toCP852(value);
+  }
+  // Pad to 20 bytes with spaces so the LCD is happy.
+  while (len < 20) {
+    result[len++] = ' ';
+  }
+  // Zero-terminate and return.
+  result[len] = '\0';
+  return String((char *) result);
+}
+
+class VF60 {
+  public:
+  VF60(HardwareSerial &serial):
+    port(serial)
+  {
+  }
+
+  void begin()
+  {
+    port.begin(9600);
+    codepage_852();
+    home();
+    clear();
+  }
+
+  void clear()
+  {
+    port.write("\x1b[2J");
+  }
+
+  void home()
+  {
+    port.write("\x1b[1;1H");
+  }
+
+  void codepage_852()
+  {
+    port.write("\x1bt\x07");
+  }
+
+  void brightness(int level)
+  {
+    port.write("\x1b\\?LD");
+    port.print(level);
+  }
+
+  void text(const String &line1, const String &line2)
+  {
+    home();
+    port.write(UTF8toCP852(line1).c_str());
+    port.write("\r\n");
+    port.write(UTF8toCP852(line2).c_str());
+  }
+
+  private:
+  HardwareSerial &port;
+};
+
+
+VF60 VF60(Serial);
+ESP8266WebServer server(80);
+
+void handleRoot() {
+  server.send(200, "text/plain",
+    "VF60 WiFi Driver\r\n"
+    "Usage:\r\n"
+    "GET /display?line1=...&line2=... (use UTF-8 encoding)\r\n"
+    "GET /brightness?level=0..5\r\n"
+  );
+}
+
+void handleDisplay() {
+  String line1 = server.arg("line1");
+  String line2 = server.arg("line2");
+  if (!line1) line1 = String();
+  if (!line2) line2 = String();
+  VF60.text(line1, line2);
+  server.send(200, "text/plain", "OK");
+}
+
+void handleBrightness() {
+  String levelStr = server.arg("level");
+  if (levelStr) {
+    int level = levelStr.toInt();
+    VF60.brightness(level);
+  }
+  server.send(200, "text/plain", "OK");
+}
+
+void setup()
+{
+    WiFi.mode(WIFI_STA);
+    WiFi.begin(ssid, password);
+    delay(1000);
+    VF60.begin();
+    VF60.text(String("12345678901234567890"), String("Zażółć Gęślą Jaźń"));
+    delay(1000);
+    VF60.clear();
+
+    server.on("/", handleRoot);
+    server.on("/display", handleDisplay);
+    server.on("/brightness", handleBrightness);
+    server.begin();
+}
+
+void loop()
+{
+  server.handleClient();
+  delay(2);
+}