Operation Manual

“buch” — 2014/9/6 — 18: 5 6 — page 16 — #12
Inhaltsverzeichnis
Der Schaltregler LM2596S ...... ......................................................................................... 374
Versorgung über den USB-Port ...................................................................................... 376
9.6 Gehäuse ................................................................................................................................ 377
The Punnet – Das kostenlose Papiergehäuse ............................................................ 377
Das Legogehäuse ................................................................................................................ 378
ModMyPi-Standardcase ................................................................................................... 378
Rail-Case – Der Raspberry Pi auf der Schiene ............................................................. 378
Multi-Pi – Das stapelbare Raspberry-Pi-Gehäuse ..................................................... 379
Designergehäuse aus edlem Holz ................................................................................. 379
Durchsichtiges Gehäuse mit Kamerahalterung ........................................................ 380
10 Elektrotechnik-Crashkurs ........ ..... ..... ..... ....... ..... ..... ...... ..... ....... ..... ..... ..... ..... .. 383
10.1 Strom, Spannung und das Ohmsche Gesetz .............................................................. 383
10.2 Grundschaltungen ............................................................................................................. 385
Darstellung der Schaltpläne ............................................................................................ 385
Reihenschaltung ................................................................................................................. 386
Parallelschaltung ................................................................................................................ 387
Kombinierte Schaltung ..................................................................................................... 387
Spannungsteiler .................................................................................................................. 389
10.3 Elektronische Grundbauteile .......................................................................................... 390
Diode ...................................................................................................................................... 390
Leuchtdiode .......................................................................................................................... 390
Kondensator ......................................................................................................................... 392
Spule ....................................................................................................................................... 392
Transistor .............................................................................................................................. 393
Relais ...................................................................................................................................... 394
10.4 Das Multimeter ................................................................................................................... 395
10.5 Breadboard oder Platine? ................................................................................................ 398
Breadboards ......................................................................................................................... 398
Streifen- oder Lochrasterplatinen .................................................................................. 399
10.6 Löten ...................................................................................................................................... 400
10.7 Breadboardadapter ........................................................................................................... 402
Breadboardadapter selbst erstellen ............................................................................. 402
Der T-Cobbler ....................................................................................................................... 406
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“buch” — 2014/9/6 — 18: 5 6 — page 17 — #13
Inhaltsverzeichnis
11 LEDs, Motoren und Relais ..... ........ ..... ..... ..... ..... ....... ...... ..... ..... ..... ....... ..... ..... .. 407
11.1 Leuchtd ioden (LEDs) .......................................................................................................... 407
LED im Dauerbetrieb ......................................................................................................... 407
LED per Python ein- und ausschalten ........................................................................... 408
LEDs über Transistoren schalten .................................................................................... 410
LEDs mit Darlington-Transistoren ansteuern ............................................................. 412
LEDs mit einem Taster ein- und ausschalten ............................................................. 413
LEDs mit Software-PWM dimmen ................................................................................ 419
LEDs mit Hardware-PWM dimmen ............................................................................... 421
Hardware PWM beim Modell B+ ................................................................................... 422
RGB-LEDs ............................................................................................................................... 422
11.2 Optokoppler ......................................................................................................................... 426
11.3 Elektromotoren ................................................................................................................... 427
Der geeignete Motor ......................................................................................................... 428
Gleichstrom- und Wechselstrommotoren .................................................................. 429
Die H-Brücke ........................................................................................................................ 430
Der Motortreiber L298 ...................................................................................................... 432
Verdrahtung und Software .............................................................................................. 434
Motordrehzahl per Software ändern ........................................................................... 438
11.4 Schrittmotoren ................................................................................................................... 440
Bipolare Ansteuerung ....................................................................................................... 441
Unipolare Ansteuerung .................................................................................................... 445
Intelligente Schrittmotortreiber .................................................................................... 447
11.5 Relais ...................................................................................................................................... 451
Relaistypen ........................................................................................................................... 451
12 Bussysteme ...... ..... ........ ..... ..... ..... ..... ........ ..... ..... ..... ..... ....... ...... ..... ..... ..... ....... ..... ..... .. 455
12.1 SPI ........................................................................................................................................... 455
SPI per raspi-config einrichten ....................................................................................... 456
SPI manuell einrichten ...................................................................................................... 457
Das digitale Potenziometer ............................................................................................. 458
Daten per SPI senden ........................................................................................................ 459
Daten per SPI lesen ............................................................................................................ 463
Der Analog-/Digitalwandler MCP3008 ........................................................................ 465
Der Digital-/Analogwandler MCP4811 ........................................................................ 470
SPI-Bauteile .......................................................................................................................... 475
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