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--- arm:teensy3 [2014/04/16 21:32] – [PWM] redox
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-# Teensy 3
-## Overview
-{{ :arm:teensy3:teensy3.png?direct&200|Teensy3}} I won't get into much details. The official website, [[http://pjrc.com/teensy/|PJRC.com]], does its job really well.
-I already had experience with the Teensy2, but I needed more power, better ADC, ... for a larger project (work, can't tell much more sorry)°. Before going for the Teensy3, I reviewed different ARM breakout boards, but I didn't need any special features or a large board.
-### Teensy3.1
-{{ :arm:teensy3:teensy31.png?direct&200|}} Shortly after I worked with the Teensy 3, PJRC released a new version, Teensy 3.1
-No more black PCB, but gold plated finish instead of tin plated. You can't have everything, right ?! It's basically a simple CPU upgrade, but you can find more details on [[http://pjrc.com/teensy/teensy31.html|this page]].
-## Tools
-### Arduino vs C
-Well, the only thing that was not really cool (__for me__) with the Teensy3 was there was no toolchain, no libraries, no tutorial whatsoever for one to start coding.
-Paul, from PJRC, has made a really great work to make the Teensy3 fully Arduino-compatible, but that was not what I was looking for. I wanted to code in pure, bare-metal C, with a GNU/Linux environment. I took me a while to understand the datasheet (1200+ pages of fun !, the Arduino libraries, ... and have my code running on the Teensy3.
-### Toolchain
-Just a quick note, it's really easy. I'm working with GNU/Linux environments, my main workstation is currently running an Archlinux x64. To start developping for ARM you need only __two__ packages, which are in the _community_ repository, so it's just:
-    sudo pacman -S arm-none-eabi-gcc arm-none-eabi-binutils
-That's all folks, you're good to go ;)
-On others distros, it should be something really close =)
-### Teensy Loader CLI
-Once again, Paul made a great USB bootloader. It's even better than the one on the Teensy2, since it's harder to brick; actually, there's a second µC on the board, that load the bootloader in RAM when you press the Reset button on the Teensy.
-You need the teensyloadercli software, but, obviously, updated for the Teensy3. It can be found in the [[http://www.pjrc.com/teensy/td_download.html|Teensyduino]] package). Usage is then really simple:
-* Start the application with the correct arguments. \\ Like ` ./teensyloadercli -mmcu=mk20dx128 -w -v YOUR_HEX.hex`
-* Press the onboard button
-* Wait until completion
-* Done !
-## LED Blink
-Or, as it's often called, the _Hello World_ for µC
-Nothing fancy, it just blinks the onboard LED on the Teensy3. The source is here: {{:arm:teensy3:tsy3_blinkled.tar.gz|Tsy3_BlinkLED}}
-Compile with `make` then program with `make program` (you need the teensyloadercli software in the source folder, I moved it system-wide later I think...). Press the button on your board, it should be flashed and then reboot. The LED blinks ! =D
-## USB
-### HID Debug
-It should work with the __hid\_listen__ software from PRJC...
-Well, blinking a LED is really cool (I _love_ LEDs)° but the Teensy3 is a bit too-much for doing just that. Moving on to USB, I really liked the usb\_debug\_only feature on the Teensy2, so I though I would do something like that for the Teensy3.
-Digging through my sources, I found I didn't separate the HID Debug and the RawHID I had to develop for the project I was working on so... no separate source here (yet, I hope to fix that someday...).
-### RawHID
-I needed some USB communication, (basically, I needed to send some data from slave devices through USB, in a portable way) so I went for Raw HID. With Full Speed USB, you can send up to 64bytes at once, no driver needed on the computer side, ...
-The code provides __usb\_debug__ (through the _hid\_listen_ tool) and __raw\_hid__ (tests with the _rawhid_ tool). It's currently available here: {{:arm:teensy3:tsy3_tsyusb_sept2k14.tar.gz|TsyUSB_Sept2014}}
-<note important>I found out later that it's not really HID compliant, and then doesn't install correctly on Windows (XP, Vista, Seven). I fixed it in the final project but not in this code. Runs fine under Linux though...</note>
-## I2C
-### Master
-### Slave
-Well, it's a little bit messy sorry, but it's old code for me; and I don't currently have time to clean things up. Two sources:
-* {{:arm:teensy3:tsy3_i2cslave.tar.gz|I2C Slave Scan OK}} \\ Basic I2C slave, can be detected when scanning the I2C bus
-* {{:arm:teensy3:tsy3_i2cslave_buffers.tar.gz|I2C Slave Buffers}} \\ Input/Ouput buffers for I2C data, quite basic though...
-## ADC
-<code>
-uint16_t ADC_Conv(uint8_t ch);
-static const uint8_t TsyADCtoARMpin[] = {
-, 14, 8, 9, 13, 12, 6, 7, 15, 4,
-, 19, 3, 21, 26, 22};
-</code>
-In your main, at initialization:
-<code>
-        uint16_t x;
-		///////////////////////// ADC - Tsy 18, 19, 20, 21, 22, 23 for ADC Inputs
-	PORTB_PCR2 = PORT_PCR_MUX(0);															  // PB2
-	PORTB_PCR3 = PORT_PCR_MUX(0);															  // PB3
-	PORTC_PCR1 = PORT_PCR_MUX(0);															  // PC1
-	PORTC_PCR2 = PORT_PCR_MUX(0);															  // PC2
-	PORTD_PCR5 = PORT_PCR_MUX(0);															  // PD5
-	PORTD_PCR6 = PORT_PCR_MUX(0);															  // PD6
-		///// VRef (Chap 33)
-	VREF_TRM = 0x60;
-	VREF_SC = _BV(7) | _BV(6) | _BV(5) | _BV(0);
-	while(!(VREF_SC & _BV(2)));				// Wait for stabilization
-		///// ADC Conf
-	SIM_SCGC6 |= SIM_SCGC6_ADC0;												// Enable ADC0 Clock
-	ADC0_CFG1 = ADC_CFG1_ADIV(3) |												// ADCK = InputClk/8
-				ADC_CFG1_ADLSMP |												 // Long Sample time
-				ADC_CFG1_MODE(3) |														// 16bit ADC
-				ADC_CFG1_ADICLK(1);											 // Input Clk = SysCLK/2
-	ADC0_CFG2 = ADC_CFG2_MUXSEL + ADC_CFG2_ADLSTS(0);			  // Channels B, longest sample time
-	ADC0_SC2 = ADC_SC2_REFSEL(0); 											// Use default VREF pins
-		///// Cal (Follows the Datasheet instructions)
-	ADC0_SC3 = ADC_SC3_CAL + ADC_SC3_AVGE + ADC_SC3_AVGS(3);
-	while(ADC0_SC3 & ADC_SC3_CAL);
-	x = 0;
-	x = ADC0_CLP0 + ADC0_CLP1 + ADC0_CLP2 + ADC0_CLP3 + ADC0_CLP4 + ADC0_CLPS;
-	x = x/2 | _BV(15);
-	ADC0_PG = x;
-	x = ADC0_CLM0 + ADC0_CLM1 + ADC0_CLM2 + ADC0_CLM3 + ADC0_CLM4 + ADC0_CLMS;
-	x = x/2 | _BV(15);
-	ADC0_MG = x;
-</code>
-After the main:
-<code>
-/* In: ADCn pin to sample
-   Out: 16bits unsigned result
-*/
-uint16_t ADC_Conv(uint8_t ch) {
-	ADC0_SC1A = TsyADCtoARMpin[ch];
-	while (!(ADC0_SC1A & ADC_SC1_COCO));
-	return ADC0_RA;
-}
-</code>
-In the main, when you need an ADC conversion:
-<code>
-TempSense = ADC_Conv(_TSY_PIN_);
-</code>
-## PWM
-<code>
-		///////////////////////// PWM
-	PORTA_PCR12 = PORT_PCR_MUX(3)|PORT_PCR_SRE;												 // PA12
-	PORTA_PCR13 = PORT_PCR_MUX(3)|PORT_PCR_SRE;												 // PA13
-	PORTC_PCR3 = PORT_PCR_MUX(4)|PORT_PCR_SRE;												 //  PC3
-	PORTD_PCR4 = PORT_PCR_MUX(4)|PORT_PCR_SRE;												 //  PD4
-	PORTD_PCR7 = PORT_PCR_MUX(4)|PORT_PCR_SRE;												 //  PD7
-	SIM_SCGC6 |= SIM_SCGC6_FTM0|SIM_SCGC6_FTM1;							 // Enable FTM0, FTM1 Clocks
-	FTM0_CNT = 0; FTM1_CNT = 0;														// Initial Value
-	FTM0_MOD = 0xFFFF; FTM1_MOD = 0xFFFF;			  // Top Value. 48MHz/TopValue = PWMfreq = 733Hz
-											   // MSnB:MSnA = 10, ELSnB:ELSnA = 10, Edge-aligned PWM
-	FTM1_C0SC = 0x28;																		 // PA12
-	FTM1_C1SC = 0x28;																		 // PA13
-	FTM0_C2SC = 0x28;																		 //  PC3
-	FTM0_C4SC = 0x28;																		 //  PD4
-	FTM0_C7SC = 0x28;																		 //  PD4
-	FTM0_SC = FTM_SC_CLKS(1) | FTM_SC_PS(0);				  			//  Use SysCLK, divided by 1
-	FTM1_SC = FTM_SC_CLKS(1) | FTM_SC_PS(0);
-	FTM0_MODE &= ~FTM_MODE_WPDIS; FTM1_MODE &= ~FTM_MODE_WPDIS;
-	FTM1_C0V = 32767; //Example
-</code>
-## Links
-* [[http://www.seanet.com/~karllunt/bareteensy31.html|Bare-metal Teensy 3.x Development]]. Featured on [[http://hackaday.com/|Hackaday]], which reminded me I still hadn't published my own code/experience...
-* [[http://hg.cmason.com/teensy3/|cmason/teensy3 - Bitbucket]] Some neat work with the Teensy3, helped when I started (and with the USB stuff too...)