path: root/nuttx/configs/pic32mx7mmb/README.txt

configs/pic32mx7mmb README
===============================

This README file discusses the port of NuttX to the  Mikroelektronika PIC32MX7
Multimedia Board (MMB)

Contents
========

  PIC32MX795F512L Pin Out
  Toolchains
  Creating Compatible NuttX HEX files
  Serial Console
  LEDs
  PIC32MX Configuration Options
  Configurations

PIC32MX795F512L Pin Out
=======================

  [This current pin-out is for the PIC32 Starter Kit and still needs to be
   updated for the  Mikroelektronika PIC32MX7 MMB]

LEFT SIDE, TOP-TO-BOTTOM (if pin 1 is in upper left)
--- ---------------------------------- -------------------------- -----------------------------------------------
PIN CONFIGURATIONS                     SIGNAL NAME                ON-BOARD CONNECTIONS
    (Family Data Sheet Table 1-1)     (Starter Kit User Guide)
--- ---------------------------------- -------------------------- -----------------------------------------------
  1 RG15/AERXERR                       ERXERR                     Ethernet RX_ER/MDIX_IN
  2 VDD                                P32_VDD                    ---
  3 PMD5/RE5                           PMPD5/RE5                  J2 pin 13
  4 PMD6/RE6                           PMPD6/RE6                  J2 pin 9
  5 PMD7/RE7                           PMPD7/RE7                  J2 pin 7
  6 RC1/T2CK                           T2CLK/RC1                  J2 pin 35 (timer)
  7 RC2/AC2TX/T3CK                     T3CLK/RC2                  J2 pin 37 (timer)
  8 RC3/AC2RX/T4CK                     T4CLK/RC3                  J2 pin 39 (timer)
  9 RC4/SDI1/T5CK                      SDI1/T4CLK/RC4             J2 pin 41 (timer)
                                                                  J2 pin 93 (SPI1)
 10 PMA5/CN8/ECOL/RG6/SCK2/U3RTS/U6TX  PMPA5/SCM2C/CN8/RG6        J2 pin 45 (SPI2)
                                                                  J2 pin 117 (PMP address)
 11 PMA4/CN9/ECRS/RG7/SDA4/SDI2/U3RX   PMPA4/SCM2A/CN9/RG7        J2 pin 47 (SPI2)
                                                                  J2 pin 119 (PMP address)
 12 PMA3/AECRSDV/AERXDV/CN10/ECRSDV/   ECRS_DV                    Ethernet CRS/CRS_DV/LED_CFG
    ERXDV/RG8/SCL4/SDO2/U3TX
 13 MCLR                               PIC32_MCLR                 (pulled up)
                                                                  PIC32MX440F512H debug processor
                                                                  J2 pin 130 (ICSP)
 14 PMA2/AEREFCLK/AERXCLK/CN11/        EREF_CLK                   50MHz clock, Ethernet X1
    EREFCLK/ERXCLK/RG9/SS2/U3CTS/
    U6RX
 15 VSS                                (grounded)                 ---
 16 VDD                                P32_VDD                    ---
 17 RA0/TMS                            TMS/RA0                    J2 pin 126 (JTAG/GPIO)
 18 AERXD0/INT1/RE8                    ERXD0(2)                   Ethernet RXD_0/PHYAD1
 19 AERXD1/INT2/RE9                    ERXD1(2)                   Ethernet RXD_1/PHYAD2
 20 AN5/C1IN+/CN7/RB5/VBUSON           VBUSON/C1IN+/AN5/CN7/RB5   USB host power supply, TPS20x1B ~EN,
                                                                  Low enables power to host port (J4) 
                                                                  USB OTG power supply, MCP1253_MSOP ~SHDN
                                                                  Enables power to device/OTG port (J5)
                                                                  J2 pin 63 (comparator 1)
                                                                  J2 pin 62 (A/D)
 21 AN4/C1IN-/CN6/RB4                  USBOEN/C1IN-/AN4/CN6/RB4   J2 pin 65 (comparator 1)
                                                                  J2 pin 64 (A/D)
 22 AN3/C2IN+/CN5/RB3                  C2IN+/AN3/CN5/RB3          TPS20x1B ~OC, sense host port power
                                                                  MCP1253_MSOP PGOOD, sense device/OTG port power
                                                                  J2 pin 67 (comparator 2)
                                                                  J2 pin 66 (A/D)
 23 AN2/C2IN-/CN4/RB2                  C2IN-/AN2/CN4/RB2          J2 pin 69 (comparator 2)
                                                                  J2 pin 101
                                                                  J2 pin 68 (A/D)
 24 AN1/CN3/PGEC1/RB1                  PGC1/AN1/CN3/RB1           J2 pin 70 (A/D)
 25 AN0/CN2/PGED1/RB0                  PGD1/AN0/CN2/RB0           J2 pin 72 (A/D)

BOTTOM SIDE, LEFT-TO-RIGHT (if pin 1 is in upper left)
--- ---------------------------------- -------------------------- -----------------------------------------------
PIN CONFIGURATIONS                     SIGNAL NAME                ON-BOARD CONNECTIONS
    (Family Data Sheet Table 1-1)     (Starter Kit User Guide)
--- ---------------------------------- -------------------------- -----------------------------------------------
 26 AN6/OCFA/PGEC2/RB6                 PIC32_PGC2                 PIC32MX440F512H debug processor
                                                                  J2 pin 128 (ICSP)
 27 AN7/PGED2/RB7                      PIC32_PGD2/DBG_SD0         PIC32MX440F512H debug processor
                                                                  J2 pin 132 (ICSP)
 28 PMA7/AERXD2/CVREF-/RA9             PMPA7/VREF-/RA9            J2 pin 113 (PMP address)
                                                                  J2 pin 114 (A/D ref)
 29 PMA6/AERXD3/CVREF+/RA10/VREF+      PMPA6/VREF+/RA10           J2 pin 115 (PMP address)
                                                                  J2 pin 116 (A/D ref)
 30 AVDD                               P32_VDD                    ---
 31 AVSS                               (grounded)                 ---
 32 AN8/C1OUT/RB8                      C1OUT/AN8/RB8              J2 pin 71
 33 AN9/C2OUT/RB9                      C2OUT/AN9/RB9              J2 pin 73
 34 PMA13/AN10/RB10/CVREFOUT           PMPA13/CVREF/AN10          J2 pin 101 (PMP address)
                                                                  J2 pin 102 (Comparator ref)
 35 PMA12/AETXERR/AN11/ERXERR/RB11     PMPA12/AN11/RB11           J2 pin 103 (PMP address)
 36 VSS                                (grounded)                 ---
 37 VDD                                P32_VDD                    ---
 38 RA1/TCK                            TCK/RA1                    PIC32MX440F512H debug processor
                                                                  J2 pin 124 (JTAG/GPIO)
 39 AC1TX/RF13/SCK4/U2RTS/U5TX         SCM3D/BCLK2/RF13           J2 pin 106 (UART2)
 40 AC1RX/RF12/SS4/U2CTS/U5RX          SCM3C/RF12                 J2 pin 108 (UART2)
 41 PMA11/AECRS/AN12/ERXD0/RB12        PMPA11/AN12/RB12           J2 pin 105 (PMP address)
 42 PMA10/AECOL/AN13/ERXD1/RB13        PMPA10/AN13/RB13           J2 pin 107 (PMP address)
 43 PMA1/AETXD3/AN14/ERXD2/PMALH/RB14  PMPA1/AN14/RB14            J2 pin 127 (PMP address)
 44 PMA0/AETXD2/AN15/CN12/ERXD3/OCFB/  PMPA0/AN15/OCFB/CN12       J2 pin 129 (PMP address)
    PMALL/RB15                                                    J2 pin 36
 45 VSS                                (grounded)                 ---
 46 VDD                                P32_VDD                    ---
 47 AETXD0/CN20/RD14/SS3/U1CTS/U4RX    EXTD0(2)                   Ethernet TXD_0
 48 AETXD1/CN21/RD15/SCK3/U1RTS/U4TX   EXTD1(2)                   Ethernet TXD_1
 49 PMA9/CN17/RF4/SDA5/SDI4/U2RX       PMPA9/SCM3A/CN17/RF4       J2 pin 109 (PMP address)
                                                                  J2 pin 110 (UART2)
 50 PMA8/CN18/RF5/SCL5/SDO4/U2TX       PMPA8/SCM3B/CN18/RF5       J2 pin 111 (PMP address)
                                                                  J2 pin 112 (UART2)

RIGHT SIDE, TOP-TO-BOTTOM (if pin 1 is in upper left)
--- ---------------------------------- -------------------------- -----------------------------------------------
PIN CONFIGURATIONS                     SIGNAL NAME                ON-BOARD CONNECTIONS
    (Family Data Sheet Table 1-1)     (Starter Kit User Guide)
--- ---------------------------------- -------------------------- -----------------------------------------------
 75 VSS                                (grounded)
 74 CN0/RC14/SOSCO/T1CK                SOSC0/T1CK/CN0/RC14        32kHz Oscillator, J2 pin (timer)
                                                                  J2 pin 32 (secondary OSC)
 73 CN1/RC13/SOSCI                     SOSC1/CN1/RC13             32kHz Oscillator
                                                                  J2 pin 32 (secondary OSC)
 72 OC1/INT0/RD0/SDO1                  SDO1/INT0/OC1/RD0          User LED D4 (high illuminates)
                                                                  J2 pin 87 (EXT_INT)
                                                                  J2 pin 95 (SPI1)
                                                                  J2 pin 46 (OC/PWM)
 71 PMA14/AEMDC/EMDC/IC4/PMCS1/RD11    EMDC                       Ethernet MDC
 70 PMA15/IC3/PMCS2/RD10/SCK1          SCK1/IC3/PMPCS2/RD10       J2 pin 29 (PMP control)
                                                                  J2 pin 91 (SPI1)
                                                                  J2 pin 52 (input capture)
 69 IC2/RD9/SS1                        SS1/IC2/RD9                J2 pin 54 (input capture)
 68 AEMDIO/EMDIO/IC1/RD8/RTCC          EMDIO                      Ethernet MDIO
 67 AETXEN/INT4/RA15/SDA1              ETXEN(2)                   Ethernet TX_EN
 66 AETXCLK/INT3/RA14/SCL1             INT3/SCL1/RA14             Ethernet PWR_DOWN/INT
 65 VSS                                (grounded)                 ---
 64 CLKO/OSC2/RC15                                                8MHz crystal
 63 CLKI/OSC1/RC12                                                8MHz crystal
 62 VDD                                P32_VDD                    ---
 61 RA5/TDO                            TDO/RA5                    PIC32MX440F512H debug processor
                                                                  J2 pin 118 (JTAG/GPIO)
 60 RA4/TDI                            TDI/RA4                    PIC32MX440F512H debug processor
 59 RA3/SDA2                           SDA2/RA3                   J2 pin 74 (I2C2)
 58 RA2/SCL2                           SCL2/RA2                   J2 pin 76 (I2C2)
 57 D+/RG2                             D+/RG2                     Host port (J4), Device OTG port (J5)
 56 D-/RG3                             D-/RG3                     Host port (J4), Device OTG port (J5)
 55 VUSB                               P32_VDD                    ---
 54 VBUS                               P32_VBUS                   ---
 53 RF8/SCL3/SDO3/U1TX                 SCM1B/RF8                  J2 pin 90 (UART1)
 52 RF2/SDA3/SDI3/U1RX                 SCM1A/RF2                  J2 pin 88 (UART1)
 51 RF3/USBID                          USBID/RF3                  Device OTG port (J5)

TOP SIDE, LEFT-TO-RIGHT (if pin 1 is in upper left)
--- ---------------------------------- -------------------------- -----------------------------------------------
PIN CONFIGURATIONS                     SIGNAL NAME                ON-BOARD CONNECTIONS
    (Family Data Sheet Table 1-1)     (Starter Kit User Guide)
--- ---------------------------------- -------------------------- -----------------------------------------------
100 PMD4/RE4                           PMPD4/RE4                  J2 pin 15 (PMP data)
 99 PMD3/RE3                           PMPD3/RE3                  J2 pin 17 (PMP data)
 98 PMD2/RE2                           PMPD2/RE2                  J2 pin 19 (PMP data)
 97 RG13/TRD0                          TRD0/RG13                  J2 pin 8 (Trace/GPIO)
 96 RG12/TRD1                          TRD1/RG12                  J2 pin 5
 95 RG14/TRD2                          TRD2/RG14                  J2 pin 3
 94 PMD1/RE1                           PMPD1/RE1                  J2 pin 21 (PMP data)
 93 PMD0/RE0                           PMPD0/RE0                  J2 pin 23 (PMP data)
 92 RA7/TRD3                           TRD3/RA7                   J2 pin 6 (Trace/GPIO)
 91 RA6/TRCLK                          TRCLK/RA6                  J2 pin 4 (Trace/GPIO)
 90 PMD8/C2RX/RG0                      PMPD8/RG0                  J2 pin 10 (PMP data)
 89 PMD9/C2TX/ETXERR/RG1               PMPD9/RG1                  J2 pin 14 (PMP data)
 88 PMD10/C1TX/ETXD0/RF1               PMPD10/RF1                 J2 pin 16 (PMP data)
 87 PMD11/C1RX/ETXD1/RF0               PMPD11/RF0                 J2 pin 18 (PMP data)
 86 VDD                                P32_VDD                    ---
 85 VCAP/VCORE                         (capacitor to ground)      ---
 84 PMD15/CN16/ETXCLK/RD7              PMPD15/CN16/RD7            Switch SW2 (low when closed)
                                                                  J2 pin 26 (PMP data)
 83 PMD14/CN15/ETXEN/RD6               PMPD14/CN15/RD6            Switch SW1 (low when closed)
                                                                  J2 pin 24 (PMP data)
 82 CN14/PMRD/RD5                      PMPRD/CN14/RD5             J2 pin 25
 81 CN13/OC5/PMWR/RD4                  PMPWR/OC5/C13/RD4          J2 pin 28 (PMP control)
                                                                  J2 pin 38
 80 PMD13/CN19/ETXD3/RD13              CN19/PMPD13/RD13           Switch SW3 (low when closed)
                                                                  J2 pin 22 (PMP data)
 79 PMD12/ETXD2/IC5/RD12               IC5/PMPD12/RD12            J2 pin 20 (PMP data)
                                                                  J2 pin 48
 78 OC4/RD3                            OC4/RD3                    J2 pin 40 (OC/PWM)
 77 OC3/RD2                            OC3/RD2                    User LED D5 (high illuminates)
                                                                  J2 pin 42 (OC/PWM)
 76 OC2/RD1                            OC1/RD1                    User LED D6 (high illuminates)
                                                                  J2 pin 44 (OC/PWM)

Toolchains
==========

  I am using the free, LITE version of the PIC32MX toolchain available
  for download from the microchip.com web site.  I am using the Windows
  version.  The MicroChip toolchain is the only toolchaing currently
  supported in these configurations, but it should be a simple matter to
  adapt to other toolchains by modifying the Make.defs file include in
  each configuration.

  Toolchain Options:

  CONFIG_PIC32MX_MICROCHIPW      - MicroChip full toolchain for Windows
  CONFIG_PIC32MX_MICROCHIPL      - MicroChip full toolchain for Linux
  CONFIG_PIC32MX_MICROCHIPW_LITE - MicroChip LITE toolchain for Windows
  CONFIG_PIC32MX_MICROCHIPL_LITE - MicroChip LITE toolchain for Linux

  Windows Native Toolchains
  
  NOTE:  There are several limitations to using a Windows based 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.

     Support has been added for making dependencies with the windows-native toolchains.
     That support can be enabled by modifying your Make.defs file as follows:

    -  MKDEP                = $(TOPDIR)/tools/mknulldeps.sh
    +  MKDEP                = $(TOPDIR)/tools/mkdeps.sh --winpaths "$(TOPDIR)"

     If you have problems with the dependency build (for example, if you are not
     building on C:), then you may need to modify tools/mkdeps.sh

Powering the Board
==================

  [To be provided]

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/mkpichex:
  ---------------

    There is a simple tool in the configs/pic32mx7mmb/tools directory
    that can be used to solve both issues with the nuttx.hex file.  But,
    first, you must build the the tools:

      cd configs/pic32mx7mmb/tools
      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:

      . ./setenv.sh    # Source setenv.sh.  Among other this, this script
                       # will add configs/pic32mx7mmb/tools 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.

Serial Console
==============

  [To be provided]

LEDs
====

  [This needs to be updated.  This test currently addresses the PIC32 starter kit]

  The PIC32MX Ethernet Starter kit has 3 user LEDs labeled LED1-3 on the
  board graphics (but referred to as LED4-6 in the schematic):

  PIN  User's Guide   Board Stencil   Notes
  ---  -------------  --------------  -------------------------
  RD0  "User LED D4"  "LED1 (RD0")    High illuminates (RED)
  RD2  "User LED D5"  "LED3 (RD2)"    High illuminates (YELLOW)
  RD1  "User LED D6"  "LED2 (RD1)"    High illuminates (GREEN)

  We will use the labels on the board to identify LEDs.  If CONFIG_ARCH_LEDS
  is defined, then NuttX will control these LEDs as follows:

                            ON                  OFF
  ------------------------- ---- ---- ---- ---- ---- ----
                            LED1 LED2 LED3 LED1 LED2 LED3
  ------------------------- ---- ---- ---- ---- ---- ----
  LED_STARTED            0  OFF  OFF  OFF  ---  ---  ---
  LED_HEAPALLOCATE       1  ON   OFF  N/C  ---  ---  ---
  LED_IRQSENABLED        2  OFF  ON   N/C  ---  ---  ---
  LED_STACKCREATED       3  ON   ON   N/C  ---  ---  ---
  LED_INIRQ              4  N/C  N/C  ON   N/C  N/C  OFF
  LED_SIGNAL             4  N/C  N/C  ON   N/C  N/C  OFF
  LED_ASSERTION          4  N/C  N/C  ON   N/C  N/C  OFF
  LED_PANIC              5  ON   N/C  N/C  OFF  N/C  N/C

  There are 5 additional LEDs available on the MEB.  These are not
  used by NuttX.

    RD1          LED1
    RD2          LED2
    RD3          LED3
    RC1          LED4
    RC2          LED5

PIC32MX Configuration Options
=============================

  General Architecture Settings:

    CONFIG_ARCH - Identifies the arch/ subdirectory.  This should
     be set to:

       CONFIG_ARCH=mips

    CONFIG_ARCH_family - For use in C code:

       CONFIG_ARCH_MIPS=y

    CONFIG_ARCH_architecture - For use in C code:

       CONFIG_ARCH_MIPS32=y

    CONFIG_ARCH_CHIP - Identifies the arch/*/chip subdirectory

       CONFIG_ARCH_CHIP=pic32mx

    CONFIG_ARCH_CHIP_name - For use in C code to identify the exact
       chip:

       CONFIG_ARCH_CHIP_PIC32MX795F512L=y

    CONFIG_ARCH_BOARD - Identifies the configs subdirectory and
       hence, the board that supports the particular chip or SoC.

       CONFIG_ARCH_BOARD=pic32mx7mmb

    CONFIG_ARCH_BOARD_name - For use in C code

       CONFIG_ARCH_BOARD_PIC32MX7MMB=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_DRAM_SIZE - Describes the installed DRAM (CPU SRAM in this case):

       CONFIG_DRAM_SIZE=(32*1024) (32Kb)

       There is an additional 32Kb of SRAM in AHB SRAM banks 0 and 1.

    CONFIG_DRAM_START - The start address of installed DRAM

       CONFIG_DRAM_START=0x10000000

    CONFIG_DRAM_END - Last address+1 of installed RAM

       CONFIG_DRAM_END=(CONFIG_DRAM_START+CONFIG_DRAM_SIZE)

    CONFIG_ARCH_IRQPRIO - The PIC32MXx supports interrupt prioritization

       CONFIG_ARCH_IRQPRIO=y

    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.

    PIC32MX Configuration

      CONFIG_PIC32MX_MVEC - Select muli- vs. single-vectored interrupts

    Individual subsystems can be enabled:

       CONFIG_PIC32MX_WDT            - Watchdog timer
       CONFIG_PIC32MX_T2             - Timer 2 (Timer 1 is the system time and always enabled)
       CONFIG_PIC32MX_T3             - Timer 3
       CONFIG_PIC32MX_T4             - Timer 4
       CONFIG_PIC32MX_T5             - Timer 5
       CONFIG_PIC32MX_IC1            - Input Capture 1
       CONFIG_PIC32MX_IC2            - Input Capture 2
       CONFIG_PIC32MX_IC3            - Input Capture 3
       CONFIG_PIC32MX_IC4            - Input Capture 4
       CONFIG_PIC32MX_IC5            - Input Capture 5
       CONFIG_PIC32MX_OC1            - Output Compare 1
       CONFIG_PIC32MX_OC2            - Output Compare 2
       CONFIG_PIC32MX_OC3            - Output Compare 3
       CONFIG_PIC32MX_OC4            - Output Compare 4
       CONFIG_PIC32MX_OC5            - Output Compare 5
       CONFIG_PIC32MX_I2C1           - I2C 1
       CONFIG_PIC32MX_I2C2           - I2C 2
       CONFIG_PIC32MX_I2C3           - I2C 3
       CONFIG_PIC32MX_I2C4           - I2C 4
       CONFIG_PIC32MX_I2C5           - I2C 5
       CONFIG_PIC32MX_SPI1           - SPI 1
       CONFIG_PIC32MX_SPI2           - SPI 2
       CONFIG_PIC32MX_SPI3           - SPI 3
       CONFIG_PIC32MX_SPI4           - SPI 4
       CONFIG_PIC32MX_UART1          - UART 1
       CONFIG_PIC32MX_UART2          - UART 2
       CONFIG_PIC32MX_UART3          - UART 3
       CONFIG_PIC32MX_UART4          - UART 4
       CONFIG_PIC32MX_UART5          - UART 5
       CONFIG_PIC32MX_UART6          - UART 6
       CONFIG_PIC32MX_ADC            - ADC 1
       CONFIG_PIC32MX_PMP            - Parallel Master Port
       CONFIG_PIC32MX_CM1            - Comparator 1
       CONFIG_PIC32MX_CM2            - Comparator 2
       CONFIG_PIC32MX_RTCC           - Real-Time Clock and Calendar
       CONFIG_PIC32MX_DMA            - DMA
       CONFIG_PIC32MX_FLASH          - FLASH
       CONFIG_PIC32MX_USBDEV         - USB device
       CONFIG_PIC32MX_USBHOST        - USB host
       CONFIG_PIC32MX_CAN1           - Controller area network 1
       CONFIG_PIC32MX_CAN2           - Controller area network 2
       CONFIG_PIC32MX_ETHERNET       - Ethernet

    PIC32MX Configuration Settings
    DEVCFG0:
      CONFIG_PIC32MX_DEBUGGER - Background Debugger Enable. Default 3 (disabled). The
        value 2 enables.
      CONFIG_PIC32MX_ICESEL - In-Circuit Emulator/Debugger Communication Channel Select
        Default 1 (PG2)
      CONFIG_PIC32MX_PROGFLASHWP  - Program FLASH write protect.  Default 0xff (disabled)
      CONFIG_PIC32MX_BOOTFLASHWP - Default 1 (disabled)
      CONFIG_PIC32MX_CODEWP - Default 1 (disabled)
    DEVCFG1: (All settings determined by selections in board.h)
    DEVCFG2: (All settings determined by selections in board.h)
    DEVCFG3: 
      CONFIG_PIC32MX_USBIDO - USB USBID Selection.  Default 1 if USB enabled
        (USBID pin is controlled by the USB module), but 0 (GPIO) otherwise.
      CONFIG_PIC32MX_VBUSIO - USB VBUSON Selection (Default 1 if USB enabled
        (VBUSON pin is controlled by the USB module, but 0 (GPIO) otherwise.
      CONFIG_PIC32MX_WDENABLE - Enabled watchdog on power up.  Default 0 (watchdog
        can be enabled later by software).

    The priority of interrupts may be specified.  The value ranage of
    priority is 4-31. The default (16) will be used if these any of these
    are undefined.

       CONFIG_PIC32MX_CTPRIO         - Core Timer Interrupt
       CONFIG_PIC32MX_CS0PRIO        - Core Software Interrupt 0
       CONFIG_PIC32MX_CS1PRIO        - Core Software Interrupt 1
       CONFIG_PIC32MX_INT0PRIO       - External Interrupt 0
       CONFIG_PIC32MX_INT1PRIO       - External Interrupt 1
       CONFIG_PIC32MX_INT2PRIO       - External Interrupt 2
       CONFIG_PIC32MX_INT3PRIO       - External Interrupt 3
       CONFIG_PIC32MX_INT4PRIO       - External Interrupt 4
       CONFIG_PIC32MX_FSCMPRIO       - Fail-Safe Clock Monitor
       CONFIG_PIC32MX_T1PRIO         - Timer 1 (System timer) priority
       CONFIG_PIC32MX_T2PRIO         - Timer 2 priority
       CONFIG_PIC32MX_T3PRIO         - Timer 3 priority
       CONFIG_PIC32MX_T4PRIO         - Timer 4 priority
       CONFIG_PIC32MX_T5PRIO         - Timer 5 priority
       CONFIG_PIC32MX_IC1PRIO        - Input Capture 1
       CONFIG_PIC32MX_IC2PRIO        - Input Capture 2
       CONFIG_PIC32MX_IC3PRIO        - Input Capture 3
       CONFIG_PIC32MX_IC4PRIO        - Input Capture 4
       CONFIG_PIC32MX_IC5PRIO        - Input Capture 5
       CONFIG_PIC32MX_OC1PRIO        - Output Compare 1
       CONFIG_PIC32MX_OC2PRIO        - Output Compare 2
       CONFIG_PIC32MX_OC3PRIO        - Output Compare 3
       CONFIG_PIC32MX_OC4PRIO        - Output Compare 4
       CONFIG_PIC32MX_OC5PRIO        - Output Compare 5
       CONFIG_PIC32MX_I2C1PRIO       - I2C 1
       CONFIG_PIC32MX_I2C2PRIO       - I2C 2
       CONFIG_PIC32MX_I2C3PRIO       - I2C 3
       CONFIG_PIC32MX_I2C4PRIO       - I2C 4
       CONFIG_PIC32MX_I2C5PRIO       - I2C 5
       CONFIG_PIC32MX_SPI2PRIO       - SPI 2
       CONFIG_PIC32MX_UART1PRIO      - UART 1
       CONFIG_PIC32MX_UART2PRIO      - UART 2
       CONFIG_PIC32MX_CN             - Input Change Interrupt
       CONFIG_PIC32MX_ADCPRIO        - ADC1 Convert Done
       CONFIG_PIC32MX_PMPPRIO        - Parallel Master Port
       CONFIG_PIC32MX_CM1PRIO        - Comparator 1
       CONFIG_PIC32MX_CM2PRIO        - Comparator 2
       CONFIG_PIC32MX_FSCMPRIO       - Fail-Safe Clock Monitor
       CONFIG_PIC32MX_RTCCPRIO       - Real-Time Clock and Calendar
       CONFIG_PIC32MX_DMA0PRIO       - DMA Channel 0
       CONFIG_PIC32MX_DMA1PRIO       - DMA Channel 1
       CONFIG_PIC32MX_DMA2PRIO       - DMA Channel 2
       CONFIG_PIC32MX_DMA3PRIO       - DMA Channel 3
       CONFIG_PIC32MX_DMA4PRIO       - DMA Channel 4
       CONFIG_PIC32MX_DMA5PRIO       - DMA Channel 5
       CONFIG_PIC32MX_DMA6PRIO       - DMA Channel 6
       CONFIG_PIC32MX_DMA7PRIO       - DMA Channel 7
       CONFIG_PIC32MX_FCEPRIO        - Flash Control Event
       CONFIG_PIC32MX_USBPRIO        - USB

  PIC32MXx specific device driver settings.  NOTE:  For the Ethernet
  starter kit, there is no RS-232 connector (even with the MEB).  See
  discussion above ("") for information about how you can configure
  an external MAX2232 board to get a serial console.

    CONFIG_UARTn_SERIAL_CONSOLE - selects the UARTn for the
       console and ttys0 (default is the UART0).
    CONFIG_UARTn_RXBUFSIZE - Characters are buffered as received.
       This specific the size of the receive buffer
    CONFIG_UARTn_TXBUFSIZE - Characters are buffered before
       being sent.  This specific the size of the transmit buffer
    CONFIG_UARTn_BAUD - The configure BAUD of the UART.  Must be
    CONFIG_UARTn_BITS - The number of bits.  Must be either 7 or 8.
    CONFIG_UARTn_PARTIY - 0=no parity, 1=odd parity, 2=even parity
    CONFIG_UARTn_2STOP - Two stop bits

PIC32MX specific PHY/Ethernet device driver settings

    CONFIG_PHY_KS8721 - Selects the Micrel KS8721 PHY
    CONFIG_PHY_DP83848C - Selects the National Semiconduction DP83848C PHY
    CONFIG_PHY_LAN8720 - Selects the SMSC LAN8720 PHY
    CONFIG_PHY_AUTONEG - Enable auto-negotion
    CONFIG_PHY_SPEED100 - Select 100Mbit vs. 10Mbit speed.
    CONFIG_PHY_FDUPLEX - Select full (vs. half) duplex
    CONFIG_NET_NTXDESC - Configured number of Tx descriptors. Default: 2
    CONFIG_NET_NRXDESC - Configured number of Rx descriptors. Default: 4
    CONFIG_NET_PRIORITY - Ethernet interrupt priority.  The is default is
      the higest priority.
    CONFIG_NET_WOL - Enable Wake-up on Lan (not fully implemented).
    CONFIG_NET_DUMPPACKET - Dump all received and transmitted packets.
      Also needs CONFIG_DEBUG.
    CONFIG_NET_REGDEBUG - Enabled low level register debug.  Also needs
      CONFIG_DEBUG.
    CONFIG_NET_HASH - Enable receipt of near-perfect match frames.
    CONFIG_NET_MULTICAST - Enable receipt of multicast (and unicast) frames.
      Automatically set if CONFIG_NET_IGMP is selected.

  Related DEVCFG3 Configuration Settings:
    CONFIG_PIC32MX_FETHIO: Ethernet I/O Pin Selection bit:
      1 = Default Ethernet I/O Pins
      0 = Alternate Ethernet I/O Pins
    CONFIG_PIC32MX_FMIIEN: Ethernet MII Enable bit
      1 = MII enabled
      0 = RMII enabled

  PIC32MXx USB Device Configuration

  PIC32MXx USB Host Configuration (the PIC32MX does not support USB Host)

Configurations
==============

Each PIC32MX configuration is maintained in a sudirectory and can be
selected as follow:

    cd tools
    ./configure.sh pic32mx7mmb/<subdir>
    cd -
    . ./setenv.sh

Where <subdir> is one of the following:

  ostest:
  =======
    Description.
    ------------
    This configuration directory, performs a simple OS test using
    apps/examples/ostest.

    Serial Output.
    --------------
    The OS test produces all of its test output on the serial console.
    This configuration has UART1 enabled as a serial console.  I have
    been unable to get this UART work on the MEB.  But on the Expansion
    I/O board, this maps to RX = J11 pin 41 and TX = J11 pin 43

  nsh:
  ====
    Description.
    ------------
    This is the NuttShell (NSH) using the NSH startup logic at
    apps/examples/nsh.

    Serial Output.
    --------------
    The OS test produces all of its test output on the serial console.
    This configuration has UART1 enabled as a serial console.  I have
    been unable to get this UART work on the MEB.  But on the Expansion
    I/O board, this maps to RX = J11 pin 41 and TX = J11 pin 43

    USB Configuations.
    -----------------
    Several USB device configurations can be enabled and included
    as NSH built-in built in functions.  

    To use USB device, connect the starter kit to the host using a cable
    with a Type-B micro-plug to the starter kit�s micro-A/B port J5, located
    on the bottom side of the starter kit. The other end of the cable
    must have a Type-A plug. Connect it to a USB host. Jumper JP2 should be
    removed.

    All USB device configurations require the following basic setup in
    your NuttX configuration file to enable USB device support:
 
      CONFIG_USBDEV=y         : Enable basic USB device support
      CONFIG_PIC32MX_USBDEV=y : Enable PIC32 USB device support

    examples/usbterm - This option can be enabled by uncommenting
    the following line in the appconfig file:

      CONFIGURED_APPS += examples/usbterm

    And by enabling one of the USB serial devices:

      CONFIG_PL2303=y         : Enable the Prolifics PL2303 emulation
      CONFIG_CDCACM=y         : or the CDC/ACM serial driver (not both)

    examples/cdcacm -  The examples/cdcacm program can be included as an 
    function by uncommenting the following line in the appconfig file:
    
      CONFIGURED_APPS += examples/cdcacm

    and defining the following in your .config file:

      CONFIG_CDCACM=y         : Enable the CDCACM device

    examples/usbstorage - There are some hooks in the appconfig file
    to enable the USB mass storage device.  However, this device cannot
    work until support for the SD card is also incorporated.

    Networking Configuations.
    -------------------------
    Several Networking configurations can be enabled and included
    as NSH built-in built in functions.  The following additional
    configuration settings are required:

      CONFIG_NET=y              : Enable networking support
      CONFIG_PIC32MX_ETHERNET=y : Enable the PIC32 Ethernet driver
      CONFIG_NSH_TELNET=y       : Enable the Telnet NSH console (optional)

    NOTES:
    1. This logic will assume that a network is connected.  During its
       initialization, it will try to negotiate the link speed.  If you have
       no network connected when you reset the board, there will be a long
       delay (maybe 30 seconds?) before anything happens.  That is the timeout
       before the networking finally gives up and decides that no network is
       available.

    2. This example can support an FTP client.  In order to build in FTP client
       support simply uncomment the following lines in the appconfig file (before
       configuring) or in the apps/.config file (after configuring):

       #CONFIGURED_APPS += netutils/ftpc
       #CONFIGURED_APPS += examples/ftpc

    3. This example can support an FTP server.  In order to build in FTP server
       support simply uncomment the following lines in the appconfig file (before
       configuring) or in the apps/.config file (after configuring):

       #CONFIGURED_APPS += netutils/ftpd
       #CONFIGURED_APPS += examples/ftpd

       And enable poll() support in the NuttX configuration file:

       CONFIG_DISABLE_POLL=n

  nsh2:
  =====

    This is an alternative NSH configuration.  Without the Expansion I/O board,
    there is no way to connect a serial console.  This NSH alternative supports
    only a Telnet console.  The nsh2 differs from the nsh configuration in the
    following ways:

    1. Networking is enabled:

       CONFIG_NET=y                : Enable networking support
       CONFIG_PIC32MX_ETHERNET=y   : Enable the PIC32 Ethernet driver
       CONFIG_NSH_CONSOLE=n        : Disable NSH serial console
       CONFIG_NSH_TELNET=y         : Enable the Telnet NSH console

       See apps/nshlib/README.txt for other NSH networking-related configuration
       settings.

    2. UART1 is disabled
 
      CONFIG_PIC32MX_UART1=n        : UART1 is disabled (as well as other UARTs)
      CONFIG_UART1_SERIAL_CONSOLE=n : There is no serial console

    3. The RAM log is enabled"
    
      CONFIG_SYSLOG=y             : Enables the System Logging feature.
      CONFIG_RAMLOG=y             : Enable the RAM-based logging feature.
      CONFIG_RAMLOG_CONSOLE=n     : (there is no default console device)
      CONFIG_RAMLOG_SYSLOG=y      : This enables the RAM-based logger as the
                                    system logger.

      Logging is currently set up to use 16Kb of memory:

      CONFIG_RAMLOG_CONSOLE_BUFSIZE=16384

    There are a few other configuration differences as necessary to support
    this different device configuration. Just the do the 'diff' if you are
    curious.

    NOTES:
      See the notes for the nsh configuration.  Most also apply to the nsh2
      configuration.

  Using a RAM disk and the USB MSC device with nsh and nsh2
  ---------------------------------------------------------
  Here is an experimental change to either examples/nsh or examples/nsh2
  that will create a RAM disk and attempt to export that RAM disk as a
  USB mass storage device.

  1. Changes to nuttx/.config

    a) Enable support for the PIC32 USB device

      -CONFIG_PIC32MX_USBDEV=n 
      +CONFIG_PIC32MX_USBDEV=y

    b) Enable NuttX USB device support

      -CONFIG_USBDEV=n
      +CONFIG_USBDEV=y

    c) Enable the USB MSC class driver

      -CONFIG_USBMSC=n
      +CONFIG_USBMSC=y

    d) Use a RAM disk (instead of an SD card) as the USB MSC logical unit:

      -CONFIG_EXAMPLES_USBMSC_DEVPATH1="/dev/mmcsd0"
      +CONFIG_EXAMPLES_USBMSC_DEVPATH1="/dev/ram0"

  2. Changes to nuttx/.config.

    a) Enable building of the examples/usbstorage:

      -# CONFIGURED_APPS += examples/usbstorage
      +  CONFIGURED_APPS += examples/usbstorage

  3. When NSH first comes up, you must manually create the RAM disk
     before exporting it:

    a) Create a 64Kb RAM disk at /dev/ram0:

      nsh> mkrd -s 512 128

    b) Put a FAT file system on the RAM disk:
  
      nsh> mkfatfs /dev/ram0

    b) Now the 'msconn' command will connect to the host and
       export /dev/ram0 as the USB logical unit:

      nsh> msconn

    NOTE:  This modification should be considered experimental.  IN the
    little testing I have done with it, it appears functional.  But the
    logic has not been stressed and there could still be lurking issues.
 
    Update. The following was added to the top-level TODO list:

    Title:       PIC32 USB DRIVER DOES NOT WORK WITH MASS STORAGE CLASS
    Description: The PIC32 USB driver either crashes or hangs when used with
                 the mass storage class when trying to write files to the target
                 storage device.  This usually works with debug on, but does not
                 work with debug OFF (implying some race condition?)

                 Here are some details of what I see in debugging:

                 1. The USB MSC device completes processing of a read request
                    and returns the read request to the driver.
                 2. Before the MSC device can even begin the wait for the next
                    driver, many packets come in at interrupt level.  The MSC
                    device goes to sleep (on pthread_cond_wait) with all of the
                    read buffers ready (16 in my test case).
                 3. The pthread_cond_wait() does not wake up.  This implies
                    a problem with pthread_con_wait(?).  But in other cases,
                    the MSC device does wake up, but then immediately crashes
                    because its stack is bad.
                 4. If I force the pthread_cond_wait to wake up (by using
                    pthread_cond_timedwait instead), then the thread wakes
                    up and crashes with a bad stack.

                 So far, I have no clue why this is failing.
    Status:      Open
    Priority:    High