Slides for a talk presented at the 24th meeting of the WebMontag Kassel Community

1. Embedded JavaScript
Mikrocontroller programmieren… mit JavaScript?!
Jens Siebert (@jens_siebert)
WebMontag Kassel, 11. Juni 2018
https://www.slideshare.net/JensSiebert1

2. Mikrocontroller

3. Embedded Programmierung bisher…

4. Embedded Programmierung bisher…

5. Embedded Programmierung bisher…
#define XTAL (12000000UL) /* Oscillator frequency */
#define OSC_CLK ( XTAL) /* Main oscillator frequency */
#define RTC_CLK ( 32000UL) /* RTC oscillator frequency */
#define IRC_OSC ( 4000000UL) /* Internal RC oscillator
frequency */
/* F_cco0 = (2 * M * F_in) / N */
#define __M (((PLL0CFG_Val ) & 0x7FFF) + 1)
#define __N (((PLL0CFG_Val >> 16) & 0x00FF) + 1)
#define __FCCO(__F_IN) ((2ULL * __M * __F_IN) / __N)
#define __CCLK_DIV (((CCLKCFG_Val ) & 0x00FF) + 1)
/* Determine core clock frequency according to settings */
#if (PLL0_SETUP)
#if ((CLKSRCSEL_Val & 0x03) == 1)
#define __CORE_CLK (__FCCO(OSC_CLK) / __CCLK_DIV)
#elif ((CLKSRCSEL_Val & 0x03) == 2)
#define __CORE_CLK (__FCCO(RTC_CLK) / __CCLK_DIV)
#else
#define __CORE_CLK (__FCCO(IRC_OSC) / __CCLK_DIV)
#endif
#else
#if ((CLKSRCSEL_Val & 0x03) == 1)
#define __CORE_CLK (OSC_CLK / __CCLK_DIV)
#elif ((CLKSRCSEL_Val & 0x03) == 2)
#define __CORE_CLK (RTC_CLK / __CCLK_DIV)
#else
#define __CORE_CLK (IRC_OSC / __CCLK_DIV)
#endif
#endif
uint32_t SystemCoreClock = __CORE_CLK;/*!< System Clock Frequency (Core Clock)*/
void SystemCoreClockUpdate (void) /* Get Core Clock Frequency */
{
/* Determine clock frequency according to clock register values */
if (((LPC_SC->PLL0STAT >> 24) & 3) == 3) { /* If PLL0 enabled and connected */
switch (LPC_SC->CLKSRCSEL & 0x03) {
case 0: /* Int. RC oscillator => PLL0 */
case 3: /* Reserved, default to Int. RC */
SystemCoreClock = (IRC_OSC *
((2ULL * ((LPC_SC->PLL0STAT & 0x7FFF) + 1))) /
(((LPC_SC->PLL0STAT >> 16) & 0xFF) + 1) /
((LPC_SC->CCLKCFG & 0xFF)+ 1));
break;
case 1: /* Main oscillator => PLL0 */
SystemCoreClock = (OSC_CLK *
((2ULL * ((LPC_SC->PLL0STAT & 0x7FFF) + 1))) /
(((LPC_SC->PLL0STAT >> 16) & 0xFF) + 1) /
((LPC_SC->CCLKCFG & 0xFF)+ 1));
break;
case 2: /* RTC oscillator => PLL0 */
SystemCoreClock = (RTC_CLK *
((2ULL * ((LPC_SC->PLL0STAT & 0x7FFF) + 1))) /
(((LPC_SC->PLL0STAT >> 16) & 0xFF) + 1) /
((LPC_SC->CCLKCFG & 0xFF)+ 1));
break;
}
}
else {
switch (LPC_SC->CLKSRCSEL & 0x03) {
case 0: /* Int. RC oscillator => PLL0 */
case 3: /* Reserved, default to Int. RC */
SystemCoreClock = IRC_OSC / ((LPC_SC->CCLKCFG & 0xFF)+ 1);
break;
case 1: /* Main oscillator => PLL0 */
SystemCoreClock = OSC_CLK / ((LPC_SC->CCLKCFG & 0xFF)+ 1);
break;
case 2: /* RTC oscillator => PLL0 */
SystemCoreClock = RTC_CLK / ((LPC_SC->CCLKCFG & 0xFF)+ 1);
break;
}
}
}

6. Embedded Programmierung bisher…
#include <stdint.h>
#include "LPC17xx.h“
#define CLOCK_SETUP 1
#define SCS_Val 0x00000020
#define CLKSRCSEL_Val 0x00000001
#define PLL0_SETUP 1
#ifdef MCB1700
# define PLL0CFG_Val 0x00050063
# define PLL1_SETUP 1
# define PLL1CFG_Val 0x00000023
# define CCLKCFG_Val 0x00000003
# define USBCLKCFG_Val 0x00000000
#else
# define PLL0CFG_Val 0x0000000B
# define PLL1_SETUP 0
# define PLL1CFG_Val 0x00000000
# define CCLKCFG_Val 0x00000002
# define USBCLKCFG_Val 0x00000005
#endif
#define PCLKSEL0_Val 0x00000000
#define PCLKSEL1_Val 0x00000000
#define PCONP_Val 0x042887DE
#define CLKOUTCFG_Val 0x00000000
#define FLASH_SETUP 1
#define FLASHCFG_Val 0x0000303A
#define CHECK_RANGE(val, min, max) ((val < min) || (val > max))
#define CHECK_RSVD(val, mask) (val & mask)
if (CHECK_RSVD((SCS_Val), ~0x00000030))
#error "SCS: Invalid values of reserved bits!"
#endif
#if (CHECK_RANGE((CLKSRCSEL_Val), 0, 2))
#error "CLKSRCSEL: Value out of range!"
#endif
#if (CHECK_RSVD((PLL0CFG_Val), ~0x00FF7FFF))
#error "PLL0CFG: Invalid values of reserved bits!"
#endif
#if (CHECK_RSVD((PLL1CFG_Val), ~0x0000007F))
#error "PLL1CFG: Invalid values of reserved bits!"
#endif
#if (PLL0_SETUP) /* if PLL0 is used */
#if (CCLKCFG_Val < 2) /* CCLKSEL must be greater then 1 */
#error "CCLKCFG: CCLKSEL must be greater then 1 if PLL0 is used!"
#endif
#endif
#if (CHECK_RANGE((CCLKCFG_Val), 2, 255))
#error "CCLKCFG: Value out of range!"
#endif
#if (CHECK_RSVD((USBCLKCFG_Val), ~0x0000000F))
#error "USBCLKCFG: Invalid values of reserved bits!"
#endif
#if (CHECK_RSVD((PCLKSEL0_Val), 0x000C0C00))
#error "PCLKSEL0: Invalid values of reserved bits!"
#endif
#if (CHECK_RSVD((PCLKSEL1_Val), 0x03000300))
#error "PCLKSEL1: Invalid values of reserved bits!"
#endif
#if (CHECK_RSVD((PCONP_Val), 0x10100821))
#error "PCONP: Invalid values of reserved bits!"
#endif
#if (CHECK_RSVD((CLKOUTCFG_Val), ~0x000001FF))
#error "CLKOUTCFG: Invalid values of reserved bits!"
#endif
/* Flash Accelerator Configuration ------------------------*/
#if (CHECK_RSVD((FLASHCFG_Val), ~0x0000F07F))
#error "FLASHCFG: Invalid values of reserved bits!"
#endif

7. Embedded Programmierung bisher…
void SystemInit (void)
{
#if (CLOCK_SETUP) /* Clock Setup */
LPC_SC->SCS = SCS_Val;
if (LPC_SC->SCS & (1 << 5)) { /* If Main Oscillator is enabled */
while ((LPC_SC->SCS & (1<<6)) == 0);/* Wait for Oscillator to be ready */
}
LPC_SC->CCLKCFG = CCLKCFG_Val; /* Setup Clock Divider */
/* Periphral clock must be selected before PLL0 enabling and connecting
* - according errata.lpc1768-16.March.2010 -
*/
LPC_SC->PCLKSEL0 = PCLKSEL0_Val; /* Peripheral Clock Selection */
LPC_SC->PCLKSEL1 = PCLKSEL1_Val;
#if (PLL0_SETUP)
LPC_SC->CLKSRCSEL = CLKSRCSEL_Val; /* Select Clock Source for PLL0 */
LPC_SC->PLL0CFG = PLL0CFG_Val; /* configure PLL0 */
LPC_SC->PLL0FEED = 0xAA;
LPC_SC->PLL0FEED = 0x55;
LPC_SC->PLL0CON = 0x01; /* PLL0 Enable */
LPC_SC->PLL0FEED = 0xAA;
LPC_SC->PLL0FEED = 0x55;
while (!(LPC_SC->PLL0STAT & (1<<26)));/* Wait for PLOCK0 */
LPC_SC->PLL0CON = 0x03; /* PLL0 Enable & Connect */
LPC_SC->PLL0FEED = 0xAA;
LPC_SC->PLL0FEED = 0x55;
while (!(LPC_SC->PLL0STAT & ((1<<25) | (1<<24))));/* Wait for PLLC0_STAT & PLLE0_STAT */
#endif
#if (PLL1_SETUP)
LPC_SC->PLL1CFG = PLL1CFG_Val;
LPC_SC->PLL1FEED = 0xAA;
LPC_SC->PLL1FEED = 0x55;
LPC_SC->PLL1CON = 0x01; /* PLL1 Enable */
LPC_SC->PLL1FEED = 0xAA;
LPC_SC->PLL1FEED = 0x55;
while (!(LPC_SC->PLL1STAT & (1<<10)));/* Wait for PLOCK1 */
LPC_SC->PLL1CON = 0x03; /* PLL1 Enable & Connect */
LPC_SC->PLL1FEED = 0xAA;
LPC_SC->PLL1FEED = 0x55;
while (!(LPC_SC->PLL1STAT & ((1<< 9) | (1<< 8))));/* Wait for PLLC1_STAT & PLLE1_STAT */
#else
LPC_SC->USBCLKCFG = USBCLKCFG_Val; /* Setup USB Clock Divider */
#endif
LPC_SC->PCONP = PCONP_Val; /* Power Control for Peripherals */
LPC_SC->CLKOUTCFG = CLKOUTCFG_Val; /* Clock Output Configuration */
#endif
#if (FLASH_SETUP == 1) /* Flash Accelerator Setup */
LPC_SC->FLASHCFG = (LPC_SC->FLASHCFG & ~0x0000F000) | FLASHCFG_Val;
#endif
}

8. Embedded Programmierung bisher…
- Volle Kontrolle über Hardware
- Teure (Entwicklungs-)Hardware
- Spezialwissen
- Für Hobbyanwender kaum geeignet

9. Die Revolution: Arduino!

10. Die Revolution: Arduino!
- Preiswerte Hardware
- Viel (preiswerte) Peripherie inkl. Bibliotheken verfügbar
- Für Hobbyanwender/Quereinsteiger/Rapid Prototyping gut geeignet
- Kein Debugger 

11. Und JavaScript?

12. Espruino

13. Espruino
- Preiswerte Hardware
- Viel (preiswerte) Peripherie inkl.
Bibliotheken verfügbar
- Für Hobbyanwender/Quereinsteiger/Rapid
Prototyping gut geeignet
- Debugger verfügbar 

14. Demo Time!

15. Beispiel: Temperatur
function onTimer() {
// Messwert vom Temperatursensor auslesen
var t = E.getTemperature().toFixed(1);
// Backbuffer loeschen
g.clear();
// Kleine Schriftart für die Titelzeile auswaehlen
g.setFontBitmap();
// Titelzeile zeichnen
g.drawString("Temperature:");
// Grosse Schriftart für den Messwert auswaehlen
g.setFontVector(40);
// Messwert zentriert zeichnen, 10px Abstand vom oberen Rand
g.drawString(t, (g.getWidth() - g.stringWidth(t))/2, 10);
// Backbuffer auf Display darstellen
g.flip();
}
// Messwert und Display-Inhalt alle zwei Sekunden aktualisieren
setInterval(onTimer,2000);
// Initiale Darstellung des Messwertes
onTimer();

16. Beispiel: Luftfeuchtigkeit
// I2C-Schnittstelle konfigurieren
I2C1.setup( {scl: A5, sda: A4 } );
// HTU21D-Modul laden und über I2C-Schnittstelle verbinden
var htu = require('HTU21D').connect( I2C1 );
function onTimer() {
// Messwert vom Luftfeuchtesensor auslesen
var t = htu.readHumidity().toFixed(1);
// Backbuffer loeschen
g.clear();
// Kleine Schriftart für die Titelzeile auswaehlen
g.setFontBitmap();
// Titelzeile zeichnen
g.drawString("Humidity:");
// Grosse Schriftart für den Messwert auswaehlen
g.setFontVector(40);
// Messwert zentriert zeichnen, 10px Abstand vom oberen Rand
g.drawString(t, (g.getWidth() - g.stringWidth(t))/2, 10);
// Backbuffer auf Display darstellen
g.flip();
}
// Messwert und Display-Inhalt alle zwei Sekunden aktualisieren
setInterval(onTimer,2000);
// Initiale Darstellung des Messwertes
onTimer();

17. Beispiel: Bluetooth LE
// I2C-Schnittstelle konfigurieren
I2C1.setup( {scl: A5, sda: A4 } );
// HTU21D-Modul laden und über I2C-Schnittstelle verbinden
var htu = require('HTU21D').connect( I2C1 );
// Verfuegbare BLE Services und Charakteristiken bekannt machen
NRF.setServices({
// Envrionmental Sensing Service konfigurieren
0x181A: {
// Temperatur Charakteristik konfigurieren
0x2A6E: {
readable: true,
notify: true,
writeable: false,
value: new Int16Array([E.getTemperature() * 100]).buffer
},
// Luftfeuchte Charakteristik konfigurieren
0x2A6F: {
readable: true,
notify: true,
writeable: false,
value: new Uint16Array([htu.readHumidity() * 100]).buffer
}
}
// Envrionmental Sensing Service bekannt machen
}, {advertise: ['0x181A']});
// Messwerte erfassen und Benachrichtigungen versenden
function onTimer() {
NRF.updateServices({
// Envrionmental Sensing Service aktualisieren
0x181A: {
// Temperatur Charakteristik aktualisieren
0x2A6E: {
value: new Int16Array([E.getTemperature() * 100]).buffer,
notify: true
},
// Luftfeuchte Charakteristik aktualisieren
0x2A6F: {
value: new Uint16Array([htu.readHumidity() * 100]).buffer,
notify: true
}
}
});
}
NRF.on('connect', function(addr) {
// Messwert aktualisieren und uebermitteln
setInterval(onTimer, 2000);
// Initiale Uebermittlung des Messwertes
onTimer();
});

18. Beispiel: Bluetooth LE

19. Literatur

20. Vielen Dank!
https://www.espruino.com
https://www.espruino.com/Pixl.js
Tessel: https://www.tessel.io
Neonious: https://www.neonious.com
Slides: https://www.slideshare.net/JensSiebert1
Twitter: @jens_siebert