configs/flipnclick-pic32mz README
===============================
This README file discusses the port of NuttX to the Mikroe Flip&Click
PIC32MZ board. That board features the PIC32MZ2048EFH100 MCU.
Thanks to John Legg for contributing the Flip&Click PIC32MZ board!
Contents
========
Port Status
On Board Debug Support
Creating Compatible NuttX HEX files
Tool Issues
Serial Console
SPI
LEDs
Configurations
Port Status
===========
2018-01-07: Added architecture support for the PIC32MZ2048EFH100 used on
the Flip&Click PIC32MZ board.
2018-01-08: Created the basic board configuration for the Mikroe
Flip&Click PIC32MZ board. No testing has yet been performed. At this
point, I have not even figured out how I am going to load and debug
new firmware. I need understand how the memory map is set up when used
with the mikroBootloader.
On Board Debug Support
======================
There are several debug options:
1. Using the Arduino IDE (chipKIT core). This is available on the USB-UART
port between the C and D MikroBUS sockets. Usage is described in the
Flip&Click User Manual.
I don't think trying to use the Arduino IDE is a good option.
2. Using the mikroC USB HID bootloader. This is is available on the USB
port between the A and B MikroBUS sockets. Usage is described in the
Flip&Click User Manual.
There is a simple application available at Mikroe that will allow you
to write .hex files via the USB HID bootloader. However, in order to
use the bootloader, you will have to control the memory map so that the
downloaded code does not clobber the bootloader code FLASH, data
memory, exception vectors, etc.
At this point, I have found no documentation describing how to build
the code outside of the Mikroe toolchain for use with the Mikroe
bootloader.
3. There is an undocumented and unpopulated PICKit3 connector between the
B and C mikroBUS sockets.
4. There is an undocumented and unpopulated mikroProg connector between
the A and D mikroBUS sockets.
Since 3) and 4) are undocumented, this would require some research and
would, most likely, clobber the USB HID bootloader (and possibly the
Arduino support as well).
Creating Compatible NuttX HEX files
===================================
Intel Hex Format Files:
-----------------------
When NuttX is built it will produce two files in the top-level NuttX
directory:
1) nuttx - This is an ELF file, and
2) nuttx.hex - This is an Intel Hex format file. This is controlled by
the setting CONFIG_INTELHEX_BINARY in the .config file.
The PICkit tool wants an Intel Hex format file to burn into FLASH. However,
there is a problem with the generated nutt.hex: The tool expects the nuttx.hex
file to contain physical addresses. But the nuttx.hex file generated from the
top-level make will have address in the KSEG0 and KSEG1 regions.
tools/pic32mx/mkpichex:
----------------------
There is a simple tool in the NuttX tools/pic32mx directory that can be
used to solve both issues with the nuttx.hex file. But, first, you must
build the tool:
cd tools/pic32mx
make
Now you will have an excecutable file call mkpichex (or mkpichex.exe on
Cygwin). This program will take the nutt.hex file as an input, it will
convert all of the KSEG0 and KSEG1 addresses to physical address, and
it will write the modified file, replacing the original nuttx.hex.
To use this file, you need to do the following things:
export PATH=??? # Add the NuttX tools/pic32mx directory to your
# PATH variable
make # Build nuttx and nuttx.hex
mkpichex $PWD # Convert addresses in nuttx.hex. $PWD is the path
# to the top-level build directory. It is the only
# required input to mkpichex.
Tool Issues
===========
Segger J-Link
-------------
If using a Jlink that only these versions work with PIC32:
J-Link BASE / EDU V9 or later
J-Link ULTRA+ / PRO V4 or later
This is the command to use:
JLinkGDBServer -device PIC32MZ2048EFH100 -if 2-wire-JTAG-PIC32 -speed 12000
Serial Console
==============
[REVISIT: I am not sure if the USB VCOM ports are available to the
software. That is likely another serial port option].
Convenient U[S]ARTs that may be used as the Serial console include:
1) An Arduino Serial Shield. The RX and TX pins are available on the
Arduino connector D0 and D1 pins, respectively. These are connected
to UART5, UART5_RX and UART5_TX which are RD14 and RD15, respectively.
2) Mikroe Click Serial Shield. There are four Click bus connectors with
serial ports available as follows:
Click A: UART4 UART4_RX and UART4_TX which are RG9 and RE3, respectively.
Click B: UART3 UART3_RX and UART3_TX which are RF0 and RF1, respectively.
Click C: UART1 UART1_RX and UART1_TX which are RC1 and RE5, respectively.
Click D: UART2 UART2_RX and UART2_TX which are RC3 and RC2, respectively.
Other serial ports are probably available on the Arduino connector. I
will leave that as an exercise for the interested reader.
The outputs from these pins is 3.3V. You will need to connect RS232
transceiver to get the signals to RS232 levels (or connect to the
USB virtual COM port in the case of UART0).
SPI
===
SPI3 is available on pins D10-D13 of the Arduino Shield connectors where
you would expect then. The SPI connector is configured as follows:
Pin J1 Board Signal PIC32MZ
--- -- ------------ -------
D10 8 SPI3_SCK RB14
D10 7 SPI3_MISO RB9
D11 6 SPI3_MOSI RB10
D13 5 SPI3_SS RB9
SPI1 and SPI2 are also available on the mikroBUS Click connectors (in
addition to 5V and GND). The connectivity between connectors A and B and
between C and D differs only in the chip select pin:
MikroBUS A: MikroBUS B:
Pin Board Signal PIC32MZ Pin Board Signal PIC32MZ
---- ------------ ------- ---- ------------ -------
CS SPI2_SS1 RA0 CS SPI2_SS0 RE4
SCK SPI2_SCK RG6 SCK SPI2_SCK RG6
MISO SPI2_MISO RC4 MISO SPI2_MISO RC4
MOSI SPI2_MOSI RB5 MOSI SPI2_MOSI RB5
MikroBUS C: MikroBUS D:
Pin Board Signal PIC32MZ Pin Board Signal PIC32MZ
---- ------------ ------- ---- ------------ -------
CS SPI1_SS0 RD12 CS SPI1_SS1 RD13
SCK SPI1_SCK RD1 SCK SPI1_SCK RD1
MISO SPI1_MISO RD2 MISO SPI1_MISO RD2
MOSI SPI1_MOSI RD3 MOSI SPI1_MOSI RD3
LEDs and Buttons
================
LEDs
----
There are four LEDs on the top, red side of the board. Only
one can be controlled by software:
LED L - RB14 (SPI3_SCK)
There are also four LEDs on the back, white side of the board:
LED A - RA6
LED B - RA7
LED C - RE0
LED D - RE1
A high output value illuminates the LEDs.
These LEDs are available to the application and are all available to the
application unless CONFIG_ARCH_LEDS is defined. In that case, the usage
by the board port is defined in include/board.h and src/sam_autoleds.c.
The LEDs are used to encode OS-related events as follows:
SYMBOL MEANING LED STATE
L A B C D
---------------- ----------------------- --- --- --- --- ---
LED_STARTED NuttX has been started OFF ON OFF OFF OFF
LED_HEAPALLOCATE Heap has been allocated OFF OFF ON OFF OFF
LED_IRQSENABLED Interrupts enabled OFF OFF OFF ON OFF
LED_STACKCREATED Idle stack created OFF OFF OFF OFF ON
LED_INIRQ In an interrupt GLO N/C N/C N/C N/C
LED_SIGNAL In a signal handler GLO N/C N/C N/C N/C
LED_ASSERTION An assertion failed GLO N/C N/C N/C N/C
LED_PANIC The system has crashed 2Hz N/C N/C N/C N/C
LED_IDLE MCU is is sleep mode ---- Not used -----
Thus if LED L is glowing on and all other LEDs are off (except LED D which
was left on but is no longer controlled by NuttX and so may be in any
state), NuttX has successfully booted and is, apparently, running normally
and taking interrupts. If any of LEDs A-D are statically set, then NuttX
failed to boot and the LED indicates the initialization phase where the
failure occurred. If LED L is flashing at approximately 2Hz, then a fatal
error has been detected and the system has halted.
NOTE: After booting, LEDs A-D are no longer used by the system and may
be controlled the application.
Buttons
-------
The Flip&Click PIC32MZ has 2 user push buttons labeled T1 and T2 on the
white side of the board:
PIN LED Notes
----- ---- -------------------------
RD10 T1 Sensed low when closed
RD11 T2 Sensed low when closed
The switches have external pull-up resistors. The switches are pulled high
(+3.3V) and grounded when pressed.
Configurations
==============
Information Common to All Configurations
----------------------------------------
1. Each PIC32MZ configuration is maintained in a sub-directory and can be
selected as follow:
tools/configure.sh flipnclick-pic32mz/<subdir>
Where typical options are -l to configure to build on Linux or -c to
configure for Cygwin under Linux. 'tools/configure.sh -h' will show
you all of the options.
Before building, make sure the PATH environment variable includes the
correct path to the directory than holds your toolchain binaries.
And then build NuttX by simply typing the following. At the conclusion
of the make, the nuttx binary will reside in an ELF file called, simply,
nuttx.
make
The <subdir> that is provided above as an argument to the
tools/configure.sh must be is one of the directories listed in the
following paragraph.
2. These configurations uses the mconf-based configuration tool. To
change this configurations using that tool, you should:
a. Build and install the kconfig-mconf tool. See nuttx/README.txt
see additional README.txt files in the NuttX tools repository.
b. Execute 'make menuconfig' in the top-level nuttx in order to start
the reconfiguration process.
Configuration Directories
-------------------------
Where <subdir> is one of the following:
nsh:
This is the NuttShell (NSH) using the NSH startup logic at
apps/examples/nsh.
NOTES:
1. Serial Console. UART 4 is configured as the Serial Console. This
assumes that you will be using a Mikroe RS-232 Click card in the
mikroBUS A slot. Other serial consoles may be selected by re-
configuring (see the section "Serial Consoles" above).
2. Toolchain
By default, the Pinguino MIPs tool chain is used. This toolchain
selection can easily be changed with 'make menuconfig'.
3. Default configuration: These are other things that you may want to
change in the configuration:
CONFIG_PIC32MZ_DEBUGGER_ENABLE=n : Debugger is disabled
CONFIG_PIC32MZ_TRACE_ENABLE=n : Trace is disabled
CONFIG_PIC32MZ_JTAG_ENABLE=n : JTAG is disabled
