> For the complete documentation index, see [llms.txt](https://royals6234.gitbook.io/madmachine-examples/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://royals6234.gitbook.io/madmachine-examples/examples/makerkit/mission09lcd.md). # Mission 09 LCD ## What you need ## Circuit ## Tips ## Code ### main.swift ```swift /* Mission9 “Hello World!” LCD The LCD screen will print "Hello World!" The circuit: - Use LCD Module, and connect it to I2C0 Jack. created 2019 by Orange J Try to shows the hours, minutes and seconds on the LCD. This example code is in the public domain. Visit madmachine.io for more info. */ import SwiftIO // Initialize the I2C0 and the lcd. let i2c = I2C(Id.I2C0) let lcd = LCD1602(i2c) // Set the display area and print the message on the LCD. lcd.write(x: 0, y: 0, "Hello World!") while true { } ``` ### LCD1602.swift ```swift import SwiftIO final class LCD1602 { private enum Command { static let clearDisplay: UInt8 = 0x01 static let returnHome: UInt8 = 0x02 static let entryModeSet: UInt8 = 0x04 static let displayControl: UInt8 = 0x08 static let cursorShift: UInt8 = 0x10 static let functionSet: UInt8 = 0x20 static let setCGRAMAddr: UInt8 = 0x40 static let setDDRAMAddr: UInt8 = 0x80 } private enum EntryMode { static let entryRight: UInt8 = 0x00 static let entryLeft: UInt8 = 0x02 static let entryShiftIncrement: UInt8 = 0x01 static let entryShiftDecrement: UInt8 = 0x00 } private enum Control { static let displayOn: UInt8 = 0x04 static let displayOff: UInt8 = 0x00 static let cursorOn: UInt8 = 0x02 static let cursorOff: UInt8 = 0x00 static let blinkOn: UInt8 = 0x01 static let blinkOff: UInt8 = 0x00 } private enum Shift { static let displayMove: UInt8 = 0x08 static let cursorMove: UInt8 = 0x00 static let moveRight: UInt8 = 0x04 static let moveLeft: UInt8 = 0x00 } private enum Mode { static let _8BitMode: UInt8 = 0x10 static let _4BitMode: UInt8 = 0x00 static let _2Line: UInt8 = 0x08 static let _1Line: UInt8 = 0x00 static let _5x10Dots: UInt8 = 0x04 static let _5x8Dots: UInt8 = 0x00 } let address: UInt8 = 0x3E let i2c: I2C var displayFunctionState: UInt8 var displayControlState: UInt8 var displayModeState: UInt8 var numLines: UInt8 var currLine: UInt8 convenience init(_ i2c: I2C) { self.init(i2c, 16, 2, 0) } init(_ i2c: I2C, _ cols: UInt8, _ rows: UInt8, _ dotSize: UInt8) { self.i2c = i2c displayFunctionState = 0 displayControlState = 0 displayModeState = 0 if rows > 1 { displayFunctionState |= Mode._2Line } numLines = rows currLine = 0 if dotSize != 0 && rows == 1 { displayFunctionState |= Mode._5x10Dots } writeCommand(Command.functionSet | displayFunctionState) wait(us: 4500) writeCommand(Command.functionSet | displayFunctionState) wait(us: 150) writeCommand(Command.functionSet | displayFunctionState) writeCommand(Command.functionSet | displayFunctionState) displayControlState = Control.displayOn | Control.cursorOff | Control.blinkOff turnOn() clear() displayModeState = EntryMode.entryLeft | EntryMode.entryShiftDecrement writeCommand(Command.entryModeSet | displayModeState) } func turnOn() { displayControlState |= Control.displayOn writeCommand(Command.displayControl | displayControlState) } func turnOff() { displayControlState &= ~Control.displayOn; writeCommand(Command.displayControl | displayControlState) } func clear() { writeCommand(Command.clearDisplay) wait(us: 2000) } func home() { writeCommand(Command.returnHome) wait(us: 2000) } func noCursor() { displayControlState &= ~Control.cursorOn writeCommand(Command.displayControl | displayControlState) } func cursor() { displayControlState |= Control.cursorOn writeCommand(Command.displayControl | displayControlState) } func noBlink() { displayControlState &= ~Control.blinkOn writeCommand(Command.displayControl | displayControlState) } func blink() { displayControlState |= Control.blinkOn writeCommand(Command.displayControl | displayControlState) } func scrollLeft() { writeCommand(Command.cursorShift | Shift.displayMove | Shift.moveLeft) } func scrollRight() { writeCommand(Command.cursorShift | Shift.displayMove | Shift.moveRight) } func leftToRight() { displayModeState |= EntryMode.entryLeft writeCommand(Command.entryModeSet | displayModeState) } func rightToLeft() { displayModeState &= ~EntryMode.entryLeft writeCommand(Command.entryModeSet | displayModeState) } func autoScroll() { displayModeState |= EntryMode.entryShiftIncrement writeCommand(Command.entryModeSet | displayModeState) } func noAutoScroll() { displayModeState &= ~EntryMode.entryShiftIncrement writeCommand(Command.entryModeSet | displayModeState) } func writeCommand(_ value: UInt8) { let data: [UInt8] = [0x80, value] i2c.write(data, to: address) } func clear(x: Int, y: Int, _ count: Int) { let data: [UInt8] = [0x40, 0x20] setCursor(x: x, y: y) for _ in 1...count { i2c.write(data, to: address) } setCursor(x: x, y: y) } func setCursor(x: Int, y: Int) { let val: UInt8 = y == 0 ? UInt8(x) | 0x80 : UInt8(x) | 0xc0 writeCommand(val) } func write(_ str: String) { let array: [UInt8] = Array(str.utf8) var data: [UInt8] = [0x40, 0] for item in array { data[1] = UInt8(item) i2c.write(data, to: address) } } func write(x: Int, y: Int, _ num: Int) { write(x: x, y: y, String(num)) } func write(x: Int, y: Int, _ str: String) { setCursor(x: x, y: y) write(str) } } ``` ## Video ## See Also ## References Last revision 2020/09/10 by Johnson --- # Agent Instructions This documentation is published with GitBook. GitBook is the documentation platform designed so that both humans and AI agents can read, navigate, and reason over technical content effectively. Learn more at gitbook.com. ## Querying This Documentation If you need additional information that is not directly available in this page, you can query the documentation dynamically by asking a question. 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