577 lines
19 KiB
Plaintext
577 lines
19 KiB
Plaintext
README
|
||
^^^^^
|
||
|
||
This is the README file for the port of NuttX to the PJRC Teensy++ 2.0 board.
|
||
This board is developed by http://pjrc.com/teensy/. The Teensy++ 2.0 is based
|
||
on an Atmel AT90USB1286 MCU.
|
||
|
||
Contents
|
||
^^^^^^^^
|
||
|
||
o Teensy++ 2.0 Features
|
||
o Pin Usage
|
||
o Halfkey Bootloader
|
||
o Serial Console
|
||
o SD Connection
|
||
o Toolchains
|
||
o Windows Native Toolchains
|
||
o NuttX buildroot Toolchain
|
||
o avr-libc
|
||
o Teensy++ Configuration Options
|
||
o Configurations
|
||
|
||
Teensy++ 2.0 Features
|
||
^^^^^^^^^^^^^^^^^^^^^
|
||
|
||
o Based on the 64-pin USB AVR Microcontroller AT90USB1286.
|
||
o USB Full Speed (12Mbit/s)
|
||
o USB Device Mode
|
||
o 120kbof available FLASH memory for programs.
|
||
o 8 kbytes SRAM and 4 kbytes of EEPROM
|
||
o USB powered
|
||
o 16MHz crystal
|
||
o 48 General Purpose IO Pins
|
||
|
||
Pin Usage
|
||
^^^^^^^^^
|
||
|
||
AT90USB1286 TQFP64
|
||
-- ------------------------ ---------------------------------------------
|
||
PIN SIGNAL BOARD CONNECTION
|
||
-- ------------------------ ---------------------------------------------
|
||
(left)
|
||
1 (INT.6/AIN.0) PE6 Pad E6
|
||
2 (INT.7/AIN.1/UVcon) PE7 Pad E7
|
||
3 UVcc (Voltage circutry)
|
||
4 D- USB DP
|
||
5 D+ USB DM
|
||
6 UGnd GND
|
||
7 UCap GND (via cap)
|
||
8 VBus USB VBUS
|
||
9 (IUID) PE3 N/C
|
||
10 (SS/PCINT0) PB0 Pad B0
|
||
11 (PCINT1/SCLK) PB1 Pad B1
|
||
12 (PDI/PCINT2/MOSI) PB2 Pad B2
|
||
13 (PDO/PCINT3/MISO) PB3 Pad B3
|
||
14 (PCINT4/OC.2A) PB4 Pad B4
|
||
15 (PCINT5/OC.1A) PB5 Pad B5
|
||
16 (PCINT6/OC.1B) PB6 Pad B6
|
||
(bottom)
|
||
17 (PCINT7/OC.0A/OC.1C) PB7 Pad B7
|
||
18 (INT4/TOSC1) PE4 Pad E4
|
||
19 (INT.5/TOSC2) PE5 Pad E5
|
||
20 RESET Switch pulls to ground
|
||
21 VCC VCC
|
||
22 GND GND
|
||
23 XTAL2 XTAL (16MHz)
|
||
24 XTAL1 XTAL (16MHz)
|
||
25 (OC0B/SCL/INT0) PD0 Pad D0
|
||
26 (OC2B/SDA/INT1) PD1 Pad D1
|
||
27 (RXD1/INT2) PD2 Pad D2
|
||
28 (TXD1/INT3) PD3 Pad D3
|
||
29 (ICP1) PD4 Pad D4
|
||
30 (XCK1) PD5 Pad D5
|
||
31 (T1) PD6 Pad D6, LED
|
||
32 (T0) PD7 Pad D7
|
||
(right)
|
||
48 PA3 (AD3) Pad A3
|
||
47 PA4 (AD4) Pad A4
|
||
46 PA5 (AD5) Pad A5
|
||
45 PA6 (AD6) Pad A6
|
||
44 PA7 (AD7) Pad A7
|
||
43 PE2 (ALE/HWB) Pad ALE (Pulled down)
|
||
42 PC7 (A15/IC.3/CLKO) Pad C7
|
||
41 PC6 (A14/OC.3A) Pad C6
|
||
40 PC5 (A13/OC.3B) Pad C5
|
||
39 PC4 (A12/OC.3C) Pad C4
|
||
38 PC3 (A11/T.3) Pad C3
|
||
37 PC2 (A10) Pad C2
|
||
36 PC1 (A9) Pad C1
|
||
35 PC0 (A8) Pad C0
|
||
34 PE1 (RD) Pad E1
|
||
33 PE0 (WR) Pad E0
|
||
(top)
|
||
64 AVCC VCC
|
||
63 GND GND
|
||
62 AREF Pad Ref (Capacitor to ground)
|
||
61 PF0 (ADC0) Pad F0
|
||
60 PF1 (ADC1) Pad F1
|
||
59 PF2 (ADC2) Pad F2
|
||
58 PF3 (ADC3) Pad F3
|
||
57 PF4 (ADC4/TCK) Pad F4
|
||
56 PF5 (ADC5/TMS) Pad F5
|
||
55 PF6 (ADC6/TDO) Pad F6
|
||
54 PF7 (ADC7/TDI) Pad F7
|
||
53 GND GND
|
||
52 VCC VCC
|
||
51 PA0 (AD0) Pad A0
|
||
50 PA1 (AD1) Pad A1
|
||
49 PA2 (AD2) Pad A2
|
||
|
||
Halfkey Bootloader
|
||
^^^^^^^^^^^^^^^^^^
|
||
|
||
o Download the Teensy application from http://pjrc.com/teensy/loader.html
|
||
o Instructions are available for your OS at that places as well.
|
||
|
||
Summary:
|
||
|
||
1. Start Teensy
|
||
2. Press button on the Teensy board
|
||
3. Select a HEX file (File menu)
|
||
4. Select "program" (Operations menu)
|
||
5. Reboot (Operations menu).
|
||
|
||
Serial Console
|
||
^^^^^^^^^^^^^^
|
||
|
||
A serial console is supported on an external MAX232/MAX3232 Connected
|
||
on PD2 and PD3:
|
||
|
||
Port D, Bit 2: RXD1, Receive Data (Data input pin for the USART1). When
|
||
the USART1 receiver is enabled this pin is configured as an input
|
||
regardless of the value of DDD2. When the USART forces this pin to
|
||
be an input, the pull-up can still be controlled by the PORTD2 bit.
|
||
Port D, Bit 3: TXD1, Transmit Data (Data output pin for the USART1).
|
||
When the USART1 Transmitter is enabled, this pin is configured as
|
||
an output regardless of the value of DDD3.
|
||
|
||
AT90USB90128/64 TQFP64
|
||
-- ------------------------ ---------------------------------------------
|
||
PIN SIGNAL BOARD CONNECTION
|
||
-- ------------------------ ---------------------------------------------
|
||
27 (RXD1/INT2) PD2 Pad D2
|
||
28 (TXD1/INT3) PD3 Pad D3
|
||
|
||
Plus power and ground. There are numerous ground points and both USB 5V
|
||
and Vcc are available.
|
||
|
||
SD Connection
|
||
^^^^^^^^^^^^^
|
||
|
||
I have the SD-ADP SD/MMC Card Adaptor from www.gravitech.com
|
||
(http://www.gravitech.us/sdcaad.html). Features:
|
||
|
||
o On-board 3.3V regulator
|
||
o Connect directly to 3.3V or 5.0V microcontroller
|
||
o Card detect LED
|
||
o Includes 11-pin male header
|
||
o Board dimension: 2.0<EFBFBD>x1.3<EFBFBD>
|
||
|
||
SD-ADP Pinout / SD Connection
|
||
|
||
-- ---- ----------- -------------------------------------------------------
|
||
J2 NAME SD CARD DESCRIPTION
|
||
-- ---- ----------- -------------------------------------------------------
|
||
1 VIN (reguator) Input power to the SD card (3.3V to 6.0V)
|
||
2 GND 3,6,12,13 Common (Connects to the housing of the SD socket)
|
||
3 3V3 4 3.3V Output voltage from the on-board 3.3V regulator (250mA)
|
||
4 NC 9 NC Connect to pin 9 on the SD card (not used in SPI mode)
|
||
5 CS 1 DAT3/CS Chip select *
|
||
6 DI 2 CMD/DI Serial input data *
|
||
7 SCK 5 SCK Serial clock *
|
||
8 DO 7 DAT0/DO Serial output data
|
||
9 IRQ 8 DAT1/IRQ Interrupt request, connect to pin 8 on the SD card (not used in SPI mode)
|
||
10 CD 10 CD Card detect (active low)
|
||
11 WP 11 WP Write protect
|
||
-- ---- ----------- -------------------------------------------------------
|
||
|
||
* Via a 74LCX245 level translator / buff
|
||
|
||
Teensy SPI Connection
|
||
|
||
-- ---- -- ------------------------- -------
|
||
J2 NAME PIN NAME PAD
|
||
-- ---- -- ------------------------- -------
|
||
1 VIN -- Connected to USB +5V
|
||
2 GND -- Connected to USB GND
|
||
3 3V3 -- Not used ---
|
||
4 NC -- Not used
|
||
5 CS 10 (SS/PCINT0) PB0 Pad B0
|
||
6 DI 12 (PDI/PCINT2/MOSI) PB2 Pad B2
|
||
7 SCK 11 (PCINT1/SCLK) PB1 Pad B1
|
||
8 DO 13 (PDO/PCINT3/MISO) PB3 Pad B3
|
||
9 IRQ -- Not used ---
|
||
10 CD 14 (PCINT4/OC.2A) PB4 Pad B4
|
||
11 WP 15 (PCINT5/OC.1A) PB5 Pad B5
|
||
-- ---- -- ------------------------- -------
|
||
|
||
Toolchains
|
||
^^^^^^^^^^
|
||
|
||
There are several toolchain options. However, testing has been performed
|
||
using *only* the NuttX buildroot toolchain described below. Therefore,
|
||
the NuttX buildroot toolchain is the recommended choice.
|
||
|
||
The toolchain may be selected using the kconfig-mconf tool (via 'make menuconfig'),
|
||
by editing the existing configuration file (defconfig), or by overriding
|
||
the toolchain on the make commandline with CONFIG_AVR_TOOLCHAIN=<toolchain>.
|
||
|
||
The valid values for <toolchain> are BUILDROOT, CROSSPACK, LINUXGCC and WINAVR.
|
||
|
||
Buildroot:
|
||
|
||
There is a DIY buildroot version for the AVR boards here:
|
||
http://sourceforge.net/projects/nuttx/files/buildroot/. See the
|
||
following section for details on building this toolchain.
|
||
|
||
It is assumed in some places that buildroot toolchain is available
|
||
at ../misc/buildroot/build_avr. Edit the setenv.sh file if
|
||
this is not the case.
|
||
|
||
After configuring NuttX, make sure that CONFIG_AVR_BUILDROOT=y is set in your
|
||
.config file.
|
||
|
||
WinAVR:
|
||
|
||
For Cygwin development environment on Windows machines, you can use
|
||
WinAVR: http://sourceforge.net/projects/winavr/files/
|
||
|
||
It is assumed in some places that WinAVR is installed at C:/WinAVR. Edit the
|
||
setenv.sh file if this is not the case.
|
||
|
||
After configuring NuttX, make sure that CONFIG_AVR_WINAVR=y is set in your
|
||
.config file.
|
||
|
||
WARNING: There is an incompatible version of cygwin.dll in the WinAVR/bin
|
||
directory! Make sure that the path to the correct cygwin.dll file precedes
|
||
the path to the WinAVR binaries!
|
||
|
||
Linux:
|
||
|
||
For Linux, there are widely available avr-gcc packages. On Ubuntu, use:
|
||
sudo apt-get install gcc-avr gdb-avr avr-libc
|
||
|
||
After configuring NuttX, make sure that CONFIG_AVR_LINUXGCC=y is set in your
|
||
.config file.
|
||
|
||
Mac OS X:
|
||
|
||
For Mac OS X, the CrossPack for AVR toolchain is available from:
|
||
|
||
http://www.obdev.at/products/crosspack/index.html
|
||
|
||
This toolchain is functionally equivalent to the Linux GCC toolchain.
|
||
|
||
Windows Native Toolchains
|
||
^^^^^^^^^^^^^^^^^^^^^^^^^
|
||
|
||
The WinAVR toolchain is a Windows native toolchain. There are several
|
||
limitations to using a Windows native toolchain in a Cygwin environment.
|
||
The three biggest are:
|
||
|
||
1. The Windows toolchain cannot follow Cygwin paths. Path conversions are
|
||
performed automatically in the Cygwin makefiles using the 'cygpath'
|
||
utility but you might easily find some new path problems. If so, check
|
||
out 'cygpath -w'
|
||
|
||
2. Windows toolchains cannot follow Cygwin symbolic links. Many symbolic
|
||
links are used in Nuttx (e.g., include/arch). The make system works
|
||
around these problems for the Windows tools by copying directories
|
||
instead of linking them. But this can also cause some confusion for
|
||
you: For example, you may edit a file in a "linked" directory and find
|
||
that your changes had no effect. That is because you are building the
|
||
copy of the file in the "fake" symbolic directory. If you use a
|
||
Windows toolchain, you should get in the habit of making like this:
|
||
|
||
make clean_context all
|
||
|
||
An alias in your .bashrc file might make that less painful.
|
||
|
||
3. Dependencies are not made when using Windows versions of the GCC. This
|
||
is because the dependencies are generated using Windows pathes which do
|
||
not work with the Cygwin make.
|
||
|
||
MKDEP = $(TOPDIR)/tools/mknulldeps.sh
|
||
|
||
An additional issue with the WinAVR toolchain, in particular, is that it
|
||
contains an incompatible version of the Cygwin DLL in its bin/ directory.
|
||
You must take care that the correct Cygwin DLL is used.
|
||
|
||
NuttX buildroot Toolchain
|
||
^^^^^^^^^^^^^^^^^^^^^^^^^
|
||
|
||
If NuttX buildroot toolchain source tarball cne can be downloaded from the
|
||
NuttX SourceForge download site (https://sourceforge.net/projects/nuttx/files/).
|
||
This GNU toolchain builds and executes in the Linux or Cygwin environment.
|
||
|
||
1. You must have already configured Nuttx in <some-dir>/nuttx.
|
||
|
||
cd tools
|
||
./configure.sh Teensy++/<sub-dir>
|
||
|
||
NOTE: you also must copy avr-libc header files into the NuttX include
|
||
directory with command perhaps like:
|
||
|
||
cp -a /cygdrive/c/WinAVR/include/avr include/.
|
||
|
||
2. Download the latest buildroot package into <some-dir>
|
||
|
||
3. unpack the buildroot tarball. The resulting directory may
|
||
have versioning information on it like buildroot-x.y.z. If so,
|
||
rename <some-dir>/buildroot-x.y.z to <some-dir>/buildroot.
|
||
|
||
4. cd <some-dir>/buildroot
|
||
|
||
5. cp configs/avr-defconfig-4.5.2 .config
|
||
|
||
6. make oldconfig
|
||
|
||
7. make
|
||
|
||
8. Edit setenv.h, if necessary, so that the PATH variable includes
|
||
the path to the newly built binaries.
|
||
|
||
See the file configs/README.txt in the buildroot source tree. That has more
|
||
detailed PLUS some special instructions that you will need to follow if you
|
||
are building a toolchain for Cygwin under Windows.
|
||
|
||
avr-libc
|
||
^^^^^^^^
|
||
|
||
Header Files
|
||
|
||
In any case, header files from avr-libc are required: http://www.nongnu.org/avr-libc/.
|
||
A snapshot of avr-lib is included in the WinAVR installation. For Linux
|
||
development platforms, avr-libc package is readily available (and would
|
||
be installed in the apt-get command shown above). But if you are using
|
||
the NuttX buildroot configuration on Cygwin, then you will have to build
|
||
get avr-libc from binaries.
|
||
|
||
Header File Installation
|
||
|
||
The NuttX build will required that the AVR header files be available via
|
||
the NuttX include directory. This can be accomplished by either copying
|
||
the avr-libc header files into the NuttX include directory:
|
||
|
||
cp -a <avr-libc-path>/include/avr <nuttx-path>/include/.
|
||
|
||
Or simply using a symbolic link:
|
||
|
||
ln -s <avr-libc-path>/include/avr <nuttx-path>/include/.
|
||
|
||
Build Notes:
|
||
|
||
It may not necessary to have a built version of avr-lib; only header files
|
||
are required. Bu if you choose to use the optimized libraru functions of
|
||
the flowing point library, then you may have to build avr-lib from sources.
|
||
Below are instructions for building avr-lib from fresh sources:
|
||
|
||
1. Download the avr-libc package from:
|
||
|
||
http://savannah.nongnu.org/projects/avr-libc/
|
||
|
||
I am using avr-lib-1.7.1.tar.bz2
|
||
|
||
2. Upack the tarball and cd into the
|
||
|
||
tar jxf avr-lib-1.7.1.tar.bz2
|
||
cd avr-lib-1.7.1
|
||
|
||
3. Configure avr-lib. Assuming that WinAVR is installed at the following
|
||
location:
|
||
|
||
export PATH=/cygdrive/c/WinAVR/bin:$PATH
|
||
./configure --build=`./config.guess` --host=avr
|
||
|
||
This takes a *long* time.
|
||
|
||
4. Make avr-lib.
|
||
|
||
make
|
||
|
||
This also takes a long time because it generates variants for nearly
|
||
all AVR chips.
|
||
|
||
5. Install avr-lib.
|
||
|
||
make install
|
||
|
||
Teensy++ Configuration Options
|
||
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
|
||
|
||
CONFIG_ARCH - Identifies the arch/ subdirectory. This should
|
||
be set to:
|
||
|
||
CONFIG_ARCH=avr
|
||
|
||
CONFIG_ARCH_family - For use in C code:
|
||
|
||
CONFIG_ARCH_AVR=y
|
||
|
||
CONFIG_ARCH_architecture - For use in C code:
|
||
|
||
CONFIG_ARCH_CHIP_AT90USB=y
|
||
|
||
CONFIG_ARCH_CHIP - Identifies the arch/*/chip subdirectory
|
||
|
||
CONFIG_ARCH_CHIP=at90usb
|
||
|
||
CONFIG_ARCH_CHIP_name - For use in C code to identify the exact
|
||
chip.
|
||
|
||
CONFIG_ARCH_CHIP_AT90USB1286=y
|
||
|
||
CONFIG_ARCH_BOARD - Identifies the configs subdirectory and
|
||
hence, the board that supports the particular chip or SoC.
|
||
|
||
CONFIG_ARCH_BOARD=teensy
|
||
|
||
CONFIG_ARCH_BOARD_name - For use in C code
|
||
|
||
CONFIG_ARCH_BOARD_TEENSY=y
|
||
|
||
CONFIG_ARCH_LOOPSPERMSEC - Must be calibrated for correct operation
|
||
of delay loops
|
||
|
||
CONFIG_ENDIAN_BIG - define if big endian (default is little
|
||
endian)
|
||
|
||
CONFIG_RAM_SIZE - Describes the installed DRAM. One of:
|
||
|
||
CONFIG_RAM_SIZE=(8*1024) - (8Kb)
|
||
|
||
CONFIG_RAM_START - The start address of installed DRAM
|
||
|
||
CONFIG_RAM_START=0x800100
|
||
|
||
CONFIG_ARCH_LEDS - Use LEDs to show state. Unique to boards that
|
||
have LEDs
|
||
|
||
CONFIG_ARCH_INTERRUPTSTACK - This architecture supports an interrupt
|
||
stack. If defined, this symbol is the size of the interrupt
|
||
stack in bytes. If not defined, the user task stacks will be
|
||
used during interrupt handling.
|
||
|
||
CONFIG_ARCH_STACKDUMP - Do stack dumps after assertions
|
||
|
||
CONFIG_ARCH_LEDS - Use LEDs to show state. Unique to board architecture.
|
||
|
||
CONFIG_ARCH_CALIBRATION - Enables some build in instrumentation that
|
||
cause a 100 second delay during boot-up. This 100 second delay
|
||
serves no purpose other than it allows you to calibratre
|
||
CONFIG_ARCH_LOOPSPERMSEC. You simply use a stop watch to measure
|
||
the 100 second delay then adjust CONFIG_ARCH_LOOPSPERMSEC until
|
||
the delay actually is 100 seconds.
|
||
|
||
Individual subsystems can be enabled:
|
||
|
||
CONFIG_AVR_INT0=n
|
||
CONFIG_AVR_INT1=n
|
||
CONFIG_AVR_INT2=n
|
||
CONFIG_AVR_INT3=n
|
||
CONFIG_AVR_INT4=n
|
||
CONFIG_AVR_INT5=n
|
||
CONFIG_AVR_INT6=n
|
||
CONFIG_AVR_INT7=n
|
||
CONFIG_AVR_USBHOST=n
|
||
CONFIG_AVR_USBDEV=n
|
||
CONFIG_AVR_WDT=n
|
||
CONFIG_AVR_TIMER0=n
|
||
CONFIG_AVR_TIMER1=n
|
||
CONFIG_AVR_TIMER2=n
|
||
CONFIG_AVR_TIMER3=n
|
||
CONFIG_AVR_SPI=n
|
||
CONFIG_AVR_USART1=y
|
||
CONFIG_AVR_ANACOMP=n
|
||
CONFIG_AVR_ADC=n
|
||
CONFIG_AVR_TWI=n
|
||
|
||
If the watchdog is enabled, this specifies the initial timeout. Default
|
||
is maximum supported value.
|
||
|
||
CONFIG_WDTO_15MS
|
||
CONFIG_WDTO_30MS
|
||
CONFIG_WDTO_60MS
|
||
CONFIG_WDTO_120MS
|
||
CONFIG_WDTO_1250MS
|
||
CONFIG_WDTO_500MS
|
||
CONFIG_WDTO_1S
|
||
CONFIG_WDTO_2S
|
||
CONFIG_WDTO_4S
|
||
CONFIG_WDTO_8S
|
||
|
||
AT90USB specific device driver settings
|
||
|
||
CONFIG_USARTn_SERIAL_CONSOLE - selects the USARTn for the
|
||
console and ttys0 (default is no serial console).
|
||
CONFIG_USARTn_RXBUFSIZE - Characters are buffered as received.
|
||
This specific the size of the receive buffer
|
||
CONFIG_USARTn_TXBUFSIZE - Characters are buffered before
|
||
being sent. This specific the size of the transmit buffer
|
||
CONFIG_USARTn_BAUD - The configure BAUD of the USART. Must be
|
||
CONFIG_USARTn_BITS - The number of bits. Must be either 7 or 8.
|
||
CONFIG_USARTn_PARTIY - 0=no parity, 1=odd parity, 2=even parity
|
||
CONFIG_USARTn_2STOP - Two stop bits
|
||
|
||
AT90USB specific USB device configuration
|
||
|
||
CONFIG_USB_DISABLE_PADREGULATOR
|
||
CONFIG_USB_LOWSPEED
|
||
CONFIG_USB_NOISYVBUS
|
||
|
||
Configurations
|
||
^^^^^^^^^^^^^^
|
||
|
||
Common Configuration Notes
|
||
--------------------------
|
||
|
||
1. Each Teensy++ configuration is maintained in a sub-directory and
|
||
can be selected as follow:
|
||
|
||
cd tools
|
||
./configure.sh teensy/<subdir>
|
||
cd -
|
||
. ./setenv.sh
|
||
|
||
Where <subdir> is one of the configuration sub-directories described in
|
||
the following paragraph.
|
||
|
||
NOTE: You must also copy avr-libc header files, perhaps like:
|
||
|
||
cp -a /cygdrive/c/WinAVR/include/avr include/.
|
||
|
||
2. These configurations use the mconf-based configuration tool. To
|
||
change a configurations using that tool, you should:
|
||
|
||
a. Build and install the kconfig-mconf tool. See nuttx/README.txt
|
||
and misc/tools/
|
||
|
||
b. Execute 'make menuconfig' in nuttx/ in order to start the
|
||
reconfiguration process.
|
||
|
||
3. By default, all configurations assume the NuttX Buildroot toolchain
|
||
under Cygwin with Windows. This is easily reconfigured:
|
||
|
||
CONFIG_HOST_WINDOWS=y
|
||
CONFIG_WINDOWS_CYGWIN=y
|
||
CONFIG_AVR_BUILDROOT=y
|
||
|
||
Configuration Sub-Directories
|
||
-----------------------------
|
||
|
||
hello:
|
||
The simple apps/examples/hello "Hello, World!" example.
|
||
|
||
ostest:
|
||
This configuration directory, performs a simple OS test using
|
||
apps/examples/ostest. NOTE: The OS test is quite large. In order
|
||
to get it to fit within AVR memory constraints, it will probably be
|
||
necessary to disable some OS features.
|
||
|
||
usbmsc:
|
||
This configuration directory exercises the USB mass storage
|
||
class driver at apps/system/usbmsc. See apps/examples/README.txt
|
||
for more information.
|
||
|
||
NOTE: THIS CONFIGURATION HAS NOT YET BEEN DEBUGGED AND DOES NOT
|
||
WORK!!! ISSUES: (1) THE SPI DRIVER IS UNTESTED, (2) THE USB DRIVER
|
||
IS UNTESTED, AND (3) THE RAM USAGE MIGHT BE EXCESSIVE.
|
||
|
||
Update 7/11: (1) The SPI/SD driver has been verified, however, (2) I
|
||
believe that the current teensy/usbmsc configuration uses too
|
||
much SRAM for the system to behave sanely. A lower memory footprint
|
||
version of the mass storage driver will be required before this can
|
||
be debugged.
|
||
|