configs/pic32-starterkit README
===============================


This README file discusses the port of NuttX to the Microchip PIC32 Ethernet
Starter Kit (DM320004) with the Multimedia Expansion Board (MEB, DM320005).
See www.microchip.com for further information.

The PIC32 Ethernet Starter Kit includes:

- PIC32MX795F512L 32-bit microcontroller.
- PIC32MX795F512L USB microcontroller for on-board debugging.
- Green power indicator LED.
- Orange debug indicator LED.
- Three user-defined indicator LEDs.
- Ethernet 10/100 bus speed indicator LED.
- Three push button switches for user-defined inputs.
- On-board crystal for precision microcontroller clocking (8 MHz).
- 50 MHz Ethernet PHY oscillator.
- 32 kHz oscillator (optional).
- USB connectivity for on-board debugger communications.
- USB Host and OTG power supply for powering PIC32 USB applications.
- USB Type A receptacle connectivity for PIC32 host-based applications.
- USB Type micro-AB receptacle for OTG and USB device connectivity for PIC32
  OTG/device-based applications.
- RJ-45 Ethernet port (External Ethernet PHY).

The MEB adds:

- 3.2 inch (8.1 cm) QVGA touch screen display with backlight
- Solomon Systech Graphics Controller (SSD1926)
- Five user-controlled LEDs
- Power LED
- Four-way joystick
- Fire button
- Headphone jack
- Line output jack
- Microphone input jack
- microSD card slot.
- Accelerometer and temperature sensor
- 24LC08 EEPROM.
- SPI Flash
- 24-bit audio codec
- CPLD for SPI and Chip Select configuration
- Integrated 802.11 wireless connectivity

Contents
========

  PIC32MX795F512L Pin Out
  MEB Connector
  PICtail
  Toolchains
  Powering the Board
  Creating Compatible NuttX HEX files
  Serial Console
  LEDs
  PIC32MX Configuration Options
  Configurations

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

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)

MEB Connector
=============

The following table summarizes how the pins brought the the MEB through the
J2 on the Ethernet Starter Kit are mapped.  This connect is J2 on the Ethernet
Starter Kit and J3 on the MEB.

                           J3
PIC32 SIGNAL               PIN     CONNECTION
-------------------------- ------- ----------------------------------
PMPD0                      pin 23  Graphics Controller (SSD1926)
PMPD1                      pin 21  8-bit or 16-bit Data Bus
PMPD2                      pin 19
PMPD3                      pin 17
PMPD4                      pin 15
PMPD6                      pin 9
PMPD7                      pin 7
-------------------------- ------- ----------------------------------
PMPD8                      pin 10  Graphics Controller (SSD1926)
PMPD9                      pin 14  16-bit Data Bus
PMPD10                     pin 16
PMPD11                     pin 18
PMPD12                     pin 20
PMPD13                     pin 22
PMPD14                     pin 24
PMPD15                     pin 26
-------------------------- ------- ----------------------------------
                                   Graphics Controller (SSD1926)
RG13                       pin 8   Chip select
RB10                       pin 101 Register select
RC3                        pin 39  Wait line
RA10                       pin 115 Reset (see MRF24WBOMA and PICtail)
-------------------------- ------- ----------------------------------
                                   Touchscreen
RB11                       pin 103 X+
RB12                       pin 105 Y-
RB13                       pin 107 X-
RB14                       pin 127 Y+
-------------------------- ------- ----------------------------------
                                   Joystick
CN2/RB0                    pin 72  Left
CN3/RB1                    pin 70  Up
CN5/RB3                    pin 66  Down
CN6/RB4                    pin 64  Right
CN12/RB15                  pin 36  Fire
-------------------------- ------- ----------------------------------
                                   LEDs
RD1                        pin 44  LED1
RD2                        pin 42  LED2
RD3                        pin 40  LED3
RC1                        pin 35  LED4
RC2                        pin 37  LED5
-------------------------- ------- ----------------------------------
SDA2                       pin 74  I2C2 bus for BMA150, MCHP24LC08
SCL2                       pin 76  and WM8731 (see also MRF24WBOMA)
-------------------------- ------- ----------------------------------
SCK1                       pin 91  SPI1 bus for WM8731
SDI1                       pin 93
SDO1                       pin 95
-------------------------- ------- ----------------------------------
RA6                        pin 4   CPLD
RA7                        pin 6 
RG12                       pin 5
RG14                       pin 3
SCK2                       pin 45  (see MRF24WBOMA)
SDI2                       pin 47  (see MRF24WBOMA) 
SDO2                       pin 49  (see MRF24WBOMA)
RG9                        pin 51  (see MRF24WBOMA)
SCK3A                      pin 106 (see PICtail)
SDI3A                      pin 110 (see PICtail)
SDO3A                      pin 112 (see PICtail)
RF12                       pin 108 (see PICtail)
~SSI                       pin 97  (see PICtail)
RD9                        pin 54 
-------------------------- ------- ----------------------------------
INT3                       pin 81  MRF24WBOMA
RA10                       pin 115 (also Graphics Controller and PICtail)
RB8                        pin 71
-------------------------- ------- ----------------------------------
                                   PICtail J5
SDA2                       pin 74  I2C2 bus (see above)
SCL2                       pin 76  I2C2 bus (see above)
SCK2                       pin 45  (see CPLD)
SDI2                       pin 47  (see CPLD)
SDO2                       pin 49  (see CPLD)
RG9                        pin 51  (see CPLD)
U1RX                       pin 88 
U1TX                       pin 90 
~U1RTS                     pin 92
~U1CTS                     pin 94
RB9                        pin 73
RA10                       pin 115 Reset (see Graphics controller and MRF24WBOMA)
INT1                       pin 85
SCL1                       pin 84
SDA1                       pin 86  (see CPLD)
~SSI                       pin 97  (see CPLD)
U2RX                       pin 110 (see CPLD)
U2TX                       pin 112 (see CPLD)
~U2RTS                     pin 106 (see CPLD)
~U2CTS                     pin 108 (see CPLD)

PICtail
=======

The MEB brings many of the signals out via the PICtail (J5).  J5 is
a 28 pin connector bringing out signals as summarized here (J3 is the
designation of the connection to the Ethernet starter kit on the
MEB side):

--- --- ------------------------
J3  J5   Table 2-1
PIN PIN  Description
--- --- ------------------------
      1  3.3V
      2  I/O_4 (Test Point)
 76   3  SCL2
 84   4  SCL1
 74   5  SDA2
 86   6  SDA1
 47   7  SDI2/SDI2A/CN9/RG7
 97   8  SS1, WFI_SDO
 49   9  SDO2/SDO2A
     10  WFI_SDI
 45  11  SCK2/SCK2A
     12  WFI_SCK
 51  13  SS2/SS2A/RG9
     14  SS1/RB2
 88  15  U1RX/SDI1A
110  16  U2RX/SDI3A
 90  17  U1TX/RA10
112  18  U2TX/SDO3A
 92  19  U1RTS/C2OUT/AN9
106  20  U2RTS/SCK3A
 94  21  U1CTS/SDO1A
108  22  U2CTS/SS3A/RF12
 73  23  RB9/INT1/RE8
 115 25  RA10/SCK1A
     26  3.3V
 85  27  INT1/SS1/RD14
     28  GND

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
==================

  Ethernet Starter Kit:

    There are two ways to supply power to the PIC32 Ethernet Starter Kit:

      - USB bus power connected to USB debug connector J1.
      - An external application board with a regulated DC power supply that
        provides +5V can be connected to the J2 application board connector
        that is provided on the bottom side of the board.

    One green LED (D3) is provided to show that the PIC32 microcontroller
    is powered up.

  Ethernet Starter Kit with MEB:
  
    Power can be supplied to the Multimedia Expansion Board through the DC
    connector located on the Multimedia Expansion Board... By connecting 
    9-14V power supply to the DC connector, the Multimedia Expansion Board
    and starter kit will receive the proper voltages. The user can also
    supply power via the starter kit. However, if the application uses
    multiple features of the Multimedia Expansion Board, it is recommended
    to use 9-14V power supply."

On Board Debug Support
======================

  The PIC32 Ethernet Starter Kit includes a PIC32MX440F512H USB microcontroller
  that provides debugger connectivity over USB. The PIC32MX440F512H is hard-wired
  to the PIC32 device to provide two types of protocol translation:

    - I/O pins of PIC32MX440F512H to the ICSP™ pins of the PIC32
    - I/O pins of PIC32MX440F512H to the JTAG pins of the PIC32

  The PIC32 Ethernet Starter Kit currently uses the JTAG pins of the PIC32 device for
  programming and debugging.

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.ihx - This is an Intel Hex format file.  This is controlled by
       the setting CONFIG_INTELHEX_BINARY in the .config file.

    However, there are two problems with the generated nutt.ihx:
  
    1) The tool expects Intel Hex format files to be named *.hex.  This
       is not a significant issue.  However, just renaming the file to
       nuttx.hex is *not* sufficient.  There is another problem:
    2) The tool expects the nuttx.hex file to contain physical addresses.
       But the nuttx.ihx 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/pic32-starterkit/tools directory
    that can be used to solve both issues with the nuttx.ihx file.  But,
    first, you must build the the tools:

      cd configs/pic32-starterkit/tools
      make

    Now you will have an excecutable file call mkpichex (or mkpichex.exe on
    Cygwin).  This program will take the nutt.ihx file as an input, it will
    convert all of the KSEG0 and KSEG1 addresses to physical address, and
    it will write the modified file as 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/pic32-starterkit/tools to your
                       # PATH variable
      make             # Build nuttx and nuttx.ihx
      mkpichex $PWD    # Convert nuttx.ihx to nuttx.hex.  $PWD is the path
                       # to the top-level build directory.  It is the only
                       # required input to mkpichex.

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

 [[Warning:  This all sounds great, but the fact is that I have not yet
   gotten any serial UART output to work from the MEB.]]

  A serial console is not required to use NuttX.  However, all of the
  Nuttx example code in the apps/examples assumes that you have a 
  serial console.  The Ethernet Starter Kit(even with the MEB) does not
  have any RS-232 connector needed to drive the serial console.

  Raw UART signals are available at the MEB's PICtail connector, however,
  and can be connected to an external MAX2232 board to get a serial console.
  The defconfig files are set up to use UART2.  So the proper connections
  would be:

  PICtail
  PIN      FUNCTION
  -------- -----------
      1    3.3V
     16    U2RX
     18    U2TX
     28    GND

  UART1 is also brought out on the PICtail and would be connected as:

  PICtail
  PIN      FUNCTION
  -------- -----------
      1    3.3V
     15    U1RX
     17    U1TX
     28    GND
  
  Here is a summary of the tortuous routes taken by the PIC32MX UART pins:

  --- ---------------------------------- -------------------------- -------------------------
  PIN CONFIGURATIONS                     SIGNAL NAME                ON-BOARD CONNECTIONS
      (Family Data Sheet Table 1-1)     (Starter Kit User Guide)
  --- ---------------------------------- -------------------------- -------------------------

   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)
   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)
   52 RF2/SDA3/SDI3/U1RX                 SCM1A/RF2                  J2 pin  88 (UART1)
   53 RF8/SCL3/SDO3/U1TX                 SCM1B/RF8                  J2 pin  90 (UART1)

  J2 is the connector at the bottom of the Ethernet start kit that
  mates the Ethernet Starter kit to the MEB.  The MEB then makes the
  following signals available on the PICtail (J5):

  MEB Connector:

  -------------------------- ------- ----------------------------------
  Signal                     J3
  -------------------------- -------
  U1RX                       pin 88 
  U1TX                       pin 90 
  ~U1RTS                     pin 92
  ~U1CTS                     pin 94
  U2RX                       pin 110
  U2TX                       pin 112
  ~U2RTS                     pin 106
  ~U2CTS                     pin 108
  -------------------------- -------

  PICtail:

  The pins are labeled differently in Table 2-1 and in the schematic.  This is
  confusing.  I will trust Table 2-1.

  --- --- ------- --- --- -----------------
      Table 2-1       Schematic
  J3  J5           J3  J5
  PIN PIN  NAME    PIN PIN Description
  --- --- ------- ---- --- ------------
                         1  3.3V
   88  15  U1RX     88  15  SDI1A
  110  16  U2RX    110  16  SDI3A
   90  17  U1TX         17  RA10
                    90      SD01A
  112  18  U2TX    113  18  SDO3A
   92  19  U1RTS        19  C2OUT/AN9
                    92      SCK1A
  106  20  U2RTS   106  20  SCK3A
   94  21  U1CTS        21  SDO1A
                    94      SS1/RD14
  108  22  U2CTS   108  22  SS3A/RF12
       26  3.3V
       28  GND

LEDs
====

  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=pic32-starterkit

    CONFIG_ARCH_BOARD_name - For use in C code

       CONFIG_ARCH_BOARD_PIC32_STARTERKIT=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

  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 pic32-starterkit/<subdir>
    cd -
    . ./setenv.sh

Where <subdir> is one of the following:

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