569 lines
19 KiB
Plaintext
569 lines
19 KiB
Plaintext
README
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^^^^^
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This is the README file for the port of NuttX to the PJRC Teensy++ 2.0 board.
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This board is developed by http://pjrc.com/teensy/. The Teensy++ 2.0 is based
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on an Atmel AT90USB1286 MCU.
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Contents
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^^^^^^^^
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o Teensy++ 2.0 Features
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o Pin Usage
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o Halfkey Bootloader
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o Serial Console
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o SD Connection
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o Toolchains
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o Windows Native Toolchains
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o NuttX buildroot Toolchain
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o avr-libc
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o Teensy++ Configuration Options
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o Configurations
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Teensy++ 2.0 Features
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^^^^^^^^^^^^^^^^^^^^^
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o Based on the 64-pin USB AVR Microcontroller AT90USB1286.
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o USB Full Speed (12Mbit/s)
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o USB Device Mode
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o 120kbof available FLASH memory for programs.
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o 8 kbytes SRAM and 4 kbytes of EEPROM
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o USB powered
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o 16MHz crystal
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o 48 General Purpose IO Pins
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Pin Usage
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^^^^^^^^^
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AT90USB1286 TQFP64
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-- ------------------------ ---------------------------------------------
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PIN SIGNAL BOARD CONNECTION
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-- ------------------------ ---------------------------------------------
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(left)
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1 (INT.6/AIN.0) PE6 Pad E6
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2 (INT.7/AIN.1/UVcon) PE7 Pad E7
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3 UVcc (Voltage circutry)
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4 D- USB DP
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5 D+ USB DM
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6 UGnd GND
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7 UCap GND (via cap)
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8 VBus USB VBUS
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9 (IUID) PE3 N/C
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10 (SS/PCINT0) PB0 Pad B0
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11 (PCINT1/SCLK) PB1 Pad B1
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12 (PDI/PCINT2/MOSI) PB2 Pad B2
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13 (PDO/PCINT3/MISO) PB3 Pad B3
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14 (PCINT4/OC.2A) PB4 Pad B4
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15 (PCINT5/OC.1A) PB5 Pad B5
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16 (PCINT6/OC.1B) PB6 Pad B6
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(bottom)
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17 (PCINT7/OC.0A/OC.1C) PB7 Pad B7
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18 (INT4/TOSC1) PE4 Pad E4
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19 (INT.5/TOSC2) PE5 Pad E5
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20 RESET Switch pulls to ground
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21 VCC VCC
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22 GND GND
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23 XTAL2 XTAL (16MHz)
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24 XTAL1 XTAL (16MHz)
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25 (OC0B/SCL/INT0) PD0 Pad D0
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26 (OC2B/SDA/INT1) PD1 Pad D1
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27 (RXD1/INT2) PD2 Pad D2
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28 (TXD1/INT3) PD3 Pad D3
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29 (ICP1) PD4 Pad D4
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30 (XCK1) PD5 Pad D5
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31 (T1) PD6 Pad D6, LED
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32 (T0) PD7 Pad D7
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(right)
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48 PA3 (AD3) Pad A3
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47 PA4 (AD4) Pad A4
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46 PA5 (AD5) Pad A5
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45 PA6 (AD6) Pad A6
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44 PA7 (AD7) Pad A7
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43 PE2 (ALE/HWB) Pad ALE (Pulled down)
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42 PC7 (A15/IC.3/CLKO) Pad C7
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41 PC6 (A14/OC.3A) Pad C6
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40 PC5 (A13/OC.3B) Pad C5
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39 PC4 (A12/OC.3C) Pad C4
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38 PC3 (A11/T.3) Pad C3
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37 PC2 (A10) Pad C2
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36 PC1 (A9) Pad C1
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35 PC0 (A8) Pad C0
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34 PE1 (RD) Pad E1
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33 PE0 (WR) Pad E0
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(top)
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64 AVCC VCC
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63 GND GND
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62 AREF Pad Ref (Capacitor to ground)
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61 PF0 (ADC0) Pad F0
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60 PF1 (ADC1) Pad F1
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59 PF2 (ADC2) Pad F2
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58 PF3 (ADC3) Pad F3
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57 PF4 (ADC4/TCK) Pad F4
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56 PF5 (ADC5/TMS) Pad F5
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55 PF6 (ADC6/TDO) Pad F6
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54 PF7 (ADC7/TDI) Pad F7
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53 GND GND
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52 VCC VCC
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51 PA0 (AD0) Pad A0
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50 PA1 (AD1) Pad A1
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49 PA2 (AD2) Pad A2
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Halfkey Bootloader
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^^^^^^^^^^^^^^^^^^
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o Download the Teensy application from http://pjrc.com/teensy/loader.html
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o Instructions are available for your OS at that places as well.
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Summary:
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1. Start Teensy
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2. Press button on the Teensy board
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3. Select a HEX file (File menu)
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4. Select "program" (Operations menu)
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5. Reboot (Operations menu).
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Serial Console
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^^^^^^^^^^^^^^
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A serial console is supported on an external MAX232/MAX3232 Connected
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on PD2 and PD3:
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Port D, Bit 2: RXD1, Receive Data (Data input pin for the USART1). When
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the USART1 receiver is enabled this pin is configured as an input
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regardless of the value of DDD2. When the USART forces this pin to
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be an input, the pull-up can still be controlled by the PORTD2 bit.
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Port D, Bit 3: TXD1, Transmit Data (Data output pin for the USART1).
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When the USART1 Transmitter is enabled, this pin is configured as
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an output regardless of the value of DDD3.
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AT90USB90128/64 TQFP64
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-- ------------------------ ---------------------------------------------
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PIN SIGNAL BOARD CONNECTION
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-- ------------------------ ---------------------------------------------
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27 (RXD1/INT2) PD2 Pad D2
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28 (TXD1/INT3) PD3 Pad D3
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Plus power and ground. There are numerous ground points and both USB 5V
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and Vcc are available.
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SD Connection
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^^^^^^^^^^^^^
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I have the SD-ADP SD/MMC Card Adaptor from www.gravitech.com
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(http://www.gravitech.us/sdcaad.html). Features:
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o On-board 3.3V regulator
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o Connect directly to 3.3V or 5.0V microcontroller
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o Card detect LED
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o Includes 11-pin male header
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o Board dimension: 2.0"x1.3"
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SD-ADP Pinout / SD Connection
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-- ---- ----------- -------------------------------------------------------
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J2 NAME SD CARD DESCRIPTION
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-- ---- ----------- -------------------------------------------------------
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1 VIN (regulator)Input power to the SD card (3.3V to 6.0V)
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2 GND 3,6,12,13 Common (Connects to the housing of the SD socket)
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3 3V3 4 3.3V Output voltage from the on-board 3.3V regulator (250mA)
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4 NC 9 NC Connect to pin 9 on the SD card (not used in SPI mode)
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5 CS 1 DAT3/CS Chip select *
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6 DI 2 CMD/DI Serial input data *
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7 SCK 5 SCK Serial clock *
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8 DO 7 DAT0/DO Serial output data
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9 IRQ 8 DAT1/IRQ Interrupt request, connect to pin 8 on the SD card (not used in SPI mode)
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10 CD 10 CD Card detect (active low)
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11 WP 11 WP Write protect
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-- ---- ----------- -------------------------------------------------------
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* Via a 74LCX245 level translator / buff
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Teensy SPI Connection
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-- ---- -- ------------------------- -------
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J2 NAME PIN NAME PAD
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-- ---- -- ------------------------- -------
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1 VIN -- Connected to USB +5V
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2 GND -- Connected to USB GND
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3 3V3 -- Not used ---
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4 NC -- Not used
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5 CS 10 (SS/PCINT0) PB0 Pad B0
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6 DI 12 (PDI/PCINT2/MOSI) PB2 Pad B2
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7 SCK 11 (PCINT1/SCLK) PB1 Pad B1
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8 DO 13 (PDO/PCINT3/MISO) PB3 Pad B3
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9 IRQ -- Not used ---
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10 CD 14 (PCINT4/OC.2A) PB4 Pad B4
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11 WP 15 (PCINT5/OC.1A) PB5 Pad B5
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-- ---- -- ------------------------- -------
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Toolchains
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^^^^^^^^^^
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There are several toolchain options. However, testing has been performed
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using *only* the NuttX buildroot toolchain described below. Therefore,
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the NuttX buildroot toolchain is the recommended choice.
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The toolchain may be selected using the kconfig-mconf tool (via 'make menuconfig'),
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by editing the existing configuration file (defconfig), or by overriding
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the toolchain on the make commandline with CONFIG_AVR_TOOLCHAIN=<toolchain>.
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The valid values for <toolchain> are BUILDROOT, CROSSPACK, LINUXGCC and WINAVR.
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Buildroot:
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There is a DIY buildroot version for the AVR boards here:
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http://bitbucket.org/nuttx/buildroot/downloads/. See the
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following section for details on building this toolchain.
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Make sure that your PATH evirnoment variable includes the path the newly
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built binaries.
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After configuring NuttX, make sure that CONFIG_AVR_BUILDROOT_TOOLCHAIN=y is set in your
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.config file.
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WinAVR:
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For Cygwin development environment on Windows machines, you can use
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WinAVR: http://sourceforge.net/projects/winavr/files/
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Make sure that your PATH evirnoment variable includes the path the WinAvR
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binaries.
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After configuring NuttX, make sure that CONFIG_AVR_WINAVR_TOOLCHAIN=y is set in your
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.config file.
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WARNING: There is an incompatible version of cygwin.dll in the WinAVR/bin
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directory! Make sure that the path to the correct cygwin.dll file precedes
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the path to the WinAVR binaries!
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Atmel Studio
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Another option is to use the AVR toolchain provided within the Atmel Studio
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installation. Look in the Atmel/Studio directories and Program Files (x86)
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to find the tools in a subdirectory like toolchain/avr8/avr8-gnu-toolchain/bin.
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Linux:
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For Linux, there are widely available avr-gcc packages. On Ubuntu, use:
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sudo apt-get install gcc-avr gdb-avr avr-libc
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After configuring NuttX, make sure that CONFIG_AVR_LINUXGCC_TOOLCHAIN=y is set in your
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.config file.
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macOS:
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For macOS, the CrossPack for AVR toolchain is available from:
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http://www.obdev.at/products/crosspack/index.html
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This toolchain is functionally equivalent to the Linux GCC toolchain.
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Windows Native Toolchains
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^^^^^^^^^^^^^^^^^^^^^^^^^
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The WinAVR toolchain is a Windows native toolchain. There are several
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limitations to using a Windows native toolchain in a Cygwin environment.
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The three biggest are:
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1. The Windows toolchain cannot follow Cygwin paths. Path conversions are
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performed automatically in the Cygwin makefiles using the 'cygpath'
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utility but you might easily find some new path problems. If so, check
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out 'cygpath -w'
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2. Windows toolchains cannot follow Cygwin symbolic links. Many symbolic
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links are used in NuttX (e.g., include/arch). The make system works
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around these problems for the Windows tools by copying directories
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instead of linking them. But this can also cause some confusion for
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you: For example, you may edit a file in a "linked" directory and find
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that your changes had no effect. That is because you are building the
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copy of the file in the "fake" symbolic directory. If you use a
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Windows toolchain, you should get in the habit of making like this:
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make clean_context all
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An alias in your .bashrc file might make that less painful.
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An additional issue with the WinAVR toolchain, in particular, is that it
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contains an incompatible version of the Cygwin DLL in its bin/ directory.
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You must take care that the correct Cygwin DLL is used.
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NuttX buildroot Toolchain
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^^^^^^^^^^^^^^^^^^^^^^^^^
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If NuttX buildroot toolchain source tarball cne can be downloaded from the
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NuttX Bitbucket download site (https://bitbucket.org/nuttx/nuttx/downloads/).
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This GNU toolchain builds and executes in the Linux or Cygwin environment.
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1. You must have already configured NuttX in <some-dir>/nuttx.
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tools/configure.sh Teensy++:<sub-dir>
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NOTE: you also must copy avr-libc header files into the NuttX include
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directory with command perhaps like:
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cp -a /cygdrive/c/WinAVR/include/avr include/.
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2. Download the latest buildroot package into <some-dir>
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3. unpack the buildroot tarball. The resulting directory may
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have versioning information on it like buildroot-x.y.z. If so,
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rename <some-dir>/buildroot-x.y.z to <some-dir>/buildroot.
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4. cd <some-dir>/buildroot
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5. cp boards/avr-defconfig-4.5.2 .config
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6. make oldconfig
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7. make
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8. Make sure that the PATH variable includes the path to the newly built
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binaries.
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See the file boards/README.txt in the buildroot source tree. That has more
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detailed PLUS some special instructions that you will need to follow if you
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are building a toolchain for Cygwin under Windows.
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avr-libc
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^^^^^^^^
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Header Files
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In any case, header files from avr-libc are required: http://www.nongnu.org/avr-libc/.
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A snapshot of avr-lib is included in the WinAVR installation. For Linux
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development platforms, avr-libc package is readily available (and would
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be installed in the apt-get command shown above). But if you are using
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the NuttX buildroot configuration on Cygwin, then you will have to build
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get avr-libc from binaries.
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Header File Installation
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The NuttX build will required that the AVR header files be available via
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the NuttX include directory. This can be accomplished by either copying
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the avr-libc header files into the NuttX include directory:
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cp -a <avr-libc-path>/include/avr <nuttx-path>/include/.
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Or simply using a symbolic link:
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ln -s <avr-libc-path>/include/avr <nuttx-path>/include/.
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Build Notes:
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It may not necessary to have a built version of avr-lib; only header files
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are required. Bu if you choose to use the optimized libraru functions of
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the flowing point library, then you may have to build avr-lib from sources.
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Below are instructions for building avr-lib from fresh sources:
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1. Download the avr-libc package from:
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http://savannah.nongnu.org/projects/avr-libc/
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I am using avr-lib-1.7.1.tar.bz2
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2. Upack the tarball and cd into the
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tar jxf avr-lib-1.7.1.tar.bz2
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cd avr-lib-1.7.1
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3. Configure avr-lib. Assuming that WinAVR is installed at the following
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location:
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export PATH=/cygdrive/c/WinAVR/bin:$PATH
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./configure --build=`./config.guess` --host=avr
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This takes a *long* time.
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4. Make avr-lib.
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make
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This also takes a long time because it generates variants for nearly
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all AVR chips.
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5. Install avr-lib.
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make install
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Teensy++ Configuration Options
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^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
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CONFIG_ARCH - Identifies the arch/ subdirectory. This should
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be set to:
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CONFIG_ARCH=avr
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CONFIG_ARCH_family - For use in C code:
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CONFIG_ARCH_AVR=y
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CONFIG_ARCH_architecture - For use in C code:
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CONFIG_ARCH_CHIP_AT90USB=y
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CONFIG_ARCH_CHIP - Identifies the arch/*/chip subdirectory
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CONFIG_ARCH_CHIP=at90usb
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CONFIG_ARCH_CHIP_name - For use in C code to identify the exact
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chip.
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CONFIG_ARCH_CHIP_AT90USB1286=y
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CONFIG_ARCH_BOARD - Identifies the boards/ subdirectory and
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hence, the board that supports the particular chip or SoC.
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CONFIG_ARCH_BOARD=teensy-2.0
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CONFIG_ARCH_BOARD_name - For use in C code
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CONFIG_ARCH_BOARD_TEENSY_20=y
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CONFIG_ARCH_LOOPSPERMSEC - Must be calibrated for correct operation
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of delay loops
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CONFIG_ENDIAN_BIG - define if big endian (default is little
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endian)
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CONFIG_RAM_SIZE - Describes the installed DRAM. One of:
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CONFIG_RAM_SIZE=(8*1024) - (8Kb)
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CONFIG_RAM_START - The start address of installed DRAM
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CONFIG_RAM_START=0x800100
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CONFIG_ARCH_LEDS - Use LEDs to show state. Unique to boards that
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have LEDs
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CONFIG_ARCH_INTERRUPTSTACK - This architecture supports an interrupt
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stack. If defined, this symbol is the size of the interrupt
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stack in bytes. If not defined, the user task stacks will be
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used during interrupt handling.
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CONFIG_ARCH_STACKDUMP - Do stack dumps after assertions
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CONFIG_ARCH_LEDS - Use LEDs to show state. Unique to board architecture.
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Individual subsystems can be enabled:
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CONFIG_AVR_INT0=n
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CONFIG_AVR_INT1=n
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CONFIG_AVR_INT2=n
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CONFIG_AVR_INT3=n
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CONFIG_AVR_INT4=n
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CONFIG_AVR_INT5=n
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CONFIG_AVR_INT6=n
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CONFIG_AVR_INT7=n
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CONFIG_AVR_USBHOST=n
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CONFIG_AVR_USBDEV=n
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CONFIG_AVR_WDT=n
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CONFIG_AVR_TIMER0=n
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CONFIG_AVR_TIMER1=n
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CONFIG_AVR_TIMER2=n
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CONFIG_AVR_TIMER3=n
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CONFIG_AVR_SPI=n
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CONFIG_AVR_USART1=y
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CONFIG_AVR_ANACOMP=n
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CONFIG_AVR_ADC=n
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CONFIG_AVR_TWI=n
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If the watchdog is enabled, this specifies the initial timeout. Default
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is maximum supported value.
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CONFIG_WDTO_15MS
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CONFIG_WDTO_30MS
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CONFIG_WDTO_60MS
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CONFIG_WDTO_120MS
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CONFIG_WDTO_1250MS
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CONFIG_WDTO_500MS
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CONFIG_WDTO_1S
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CONFIG_WDTO_2S
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CONFIG_WDTO_4S
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CONFIG_WDTO_8S
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AT90USB specific device driver settings
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CONFIG_USARTn_SERIAL_CONSOLE - selects the USARTn for the
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console and ttys0 (default is no serial console).
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CONFIG_USARTn_RXBUFSIZE - Characters are buffered as received.
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This specific the size of the receive buffer
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CONFIG_USARTn_TXBUFSIZE - Characters are buffered before
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being sent. This specific the size of the transmit buffer
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CONFIG_USARTn_BAUD - The configure BAUD of the USART. Must be
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CONFIG_USARTn_BITS - The number of bits. Must be either 7 or 8.
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CONFIG_USARTn_PARTIY - 0=no parity, 1=odd parity, 2=even parity
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CONFIG_USARTn_2STOP - Two stop bits
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AT90USB specific USB device configuration
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CONFIG_USB_DISABLE_PADREGULATOR
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CONFIG_USB_LOWSPEED
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CONFIG_USB_NOISYVBUS
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|
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Configurations
|
|
^^^^^^^^^^^^^^
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|
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Common Configuration Notes
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|
--------------------------
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|
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1. Each Teensy++ configuration is maintained in a sub-directory and
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can be selected as follow:
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tools/configure.sh teensy-2.0:<subdir>
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Where <subdir> is one of the configuration sub-directories described in
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the following paragraph.
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NOTE: You must also copy avr-libc header files, perhaps like:
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cp -a /cygdrive/c/WinAVR/include/avr include/.
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2. These configurations use the mconf-based configuration tool. To
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change a configurations using that tool, you should:
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a. Build and install the kconfig-mconf tool. See nuttx/README.txt
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see additional README.txt files in the NuttX tools repository.
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b. Execute 'make menuconfig' in nuttx/ in order to start the
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reconfiguration process.
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3. By default, all configurations assume the NuttX Buildroot toolchain
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under Cygwin with Windows. This is easily reconfigured:
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CONFIG_HOST_WINDOWS=y
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CONFIG_WINDOWS_CYGWIN=y
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CONFIG_AVR_BUILDROOT_TOOLCHAIN=y
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Configuration Sub-Directories
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-----------------------------
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hello:
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The simple apps/examples/hello "Hello, World!" example.
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nsh:
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This is a reduce NuttShell (NSH) configuration using apps/example/nsh.
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The serial console is provided on USART1 and can be accessed via
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an external RS-232 driver as described above under "Serial Console".
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ostest:
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This configuration directory, performs a simple OS test using
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apps/examples/ostest. NOTE: The OS test is quite large. In order
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to get it to fit within AVR memory constraints, it will probably be
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necessary to disable some OS features.
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usbmsc:
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This configuration directory exercises the USB mass storage
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class driver at apps/system/usbmsc. See apps/examples/README.txt
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for more information.
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NOTE: THIS CONFIGURATION HAS NOT YET BEEN DEBUGGED AND DOES NOT
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WORK!!! ISSUES: (1) THE SPI DRIVER IS UNTESTED, (2) THE USB DRIVER
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IS UNTESTED, AND (3) THE RAM USAGE MIGHT BE EXCESSIVE.
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Update 7/11: (1) The SPI/SD driver has been verified, however, (2) I
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believe that the current teensy-2.0/usbmsc configuration uses too
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much SRAM for the system to behave sanely. A lower memory footprint
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version of the mass storage driver will be required before this can
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be debugged.
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