PICAXE MicrocontrollersAn Introduction by NearSys
What is a PICAXE?
• A family of microcontrollers• Based on the PIC microcontroller• Internally programmed with an interpreter and
communications program• Program stored in the PIC’s internal EEPROM• Interpreter operates on one instruction at a time
PICAXE Variations
PICAXE-08M2
PICAXE-14M2
PICAXE-18M2
PICAXE-20M2
PICAXE-28X2
PICAXE-40X2
PICAXE Voltages
Five volt chips, but can operate at 1.8 volts
PICAXE Multiple Programs
PICAXE-08M2
PICAXE-14M2
PICAXE-18M2
PICAXE-20M2
PICAXE-28X2
PICAXE-40X2
PICAXE Multiple Programs
PICAXE-08M2
PICAXE-14M2
PICAXE-18M2
PICAXE-20M2
PICAXE-28X2
PICAXE-40X2
PICAXE Clock Speed
PICAXE-08M2
PICAXE-14M2
PICAXE-18M2
PICAXE-20M2
PICAXE-28X2
PICAXE-40X2
PICAXE Clock Speed
PICAXE-08M2
PICAXE-14M2
PICAXE-18M2
PICAXE-20M2
PICAXE-28X2
PICAXE-40X2
PICAXE Pins
• Logic low < 1.4 V
• Up to four banks, A, B, C, and D depending on variation
• Most I/O pins are bidirectional
• Hardware interrupts on the X2
PICAXE Memory
• Program
• RAM
• Data
• Scratch Pad
PICAXE Memory
• Program
• RAM
• Data
• Scratch Pad
PICAXE Memory
• Program
• RAM (variables)
• Data
• Scratch Pad
PICAXE Memory
• Program
• RAM
• Data
• Scratch Pad
PICAXE Memory
• Program
• RAM (variables)
• Data
• Scratch Pad
Code ExamplesInput Commands
• PIN
• COUNT
• PULSIN
• SERIN
• READI2C
• READADC and READADC10
• IRIN
• RFIN
Code ExamplesOutput Commands
• HIGH and LOW• PULSOUT• SEROUT• WRITEI2C• PLAY and TUNE• SERVO• PMWOUT• IROUT• RFOUT
Code ExamplesProgram Flow Control Commands
• GOTO• GOSUB-RETURN• FOR-NEXT• DO-LOOP (UNTIL or WHILE)• IF-THEN-ELSEIF• ON-GOTO (GOSUB)• SELECT-CASE• BRANCH
Code ExamplesCommunications Commands
• I2cslave 10100000,i2cfast,i2cword
• writei2c 0,("hello")
• readi2c 0,(b0,b1,b2,b3,b4)
Code ExamplesCommunications Commands
• serout B.0, T1200_4,(“Testing”)
• serin C.1, T1200_4,(“X”),B.0, B.1, B.2
• sertxd (“Value: ,”B.5)
• serrxd (B.0, B.1, B.2, B.3)
• hsersetup b9600_4, %10
• hserout 0,(b.0)
• hserin 0,50
Code ExamplesMemory Commands
• PEEK-POKE
• READ-WRITE
• GET-PUT
EditorSelecting Mode
EditorSelecting Serial Port
EditorExample Text Program
EditorExample Flowchart Program
EditorExample Wizard
EditorExample Syntax Check
EditorDownload Program
EditorSimulate a Program
EditorDebug a Program
EditorTerminal Program
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