README ^^^^^^

README for NuttX port to the Stellaris RDK-S2E Reference Design Kit and the MDL-S2E Ethernet to Serial module.

Contents ^^^^^^^^

Stellaris RDK-S2E Reference Design Kit Stellaris MDL-S2E Reference Design Configuration Options Configurations

Stellaris RDK-S2E Reference Design Kit ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^

The Stellaris RDK-S2E Reference Design Kit includes the following features:

o MDL-S2E Ethernet to serial module o LM3S6432 in a 10 x 10 mm BGA package for reduced board size o 10/100 Mbit Ethernet port o Auto MDI/MDIX cross-over correction o Traffic and link indicators Serial ports o UART ports include RTS/CTS for flow control o UART0 has RS232 levels, transceiver runs at up to 230.4 Kbaud o UART1 has CMOS/TTL levels, can run at 1.0 Mbaud

Features of the LM3S6432 Microcontroller

o 32-bit RISC performance using ARM® Cortex™-M3 v7M architecture - 50-MHz operation - Hardware-division and single-cycle-multiplication - Integrated Nested Vectored Interrupt Controller (NVIC) - 42 interrupt channels with eight priority levels o 96 KB single-cycle flash o 32 KB single-cycle SRAM o Three general-purpose 32-bit timers o Integrated Ethernet MAC and PHY o Two fully programmable 16C550-type UARTs o Three 10-bit channels (inputs) when used as single-ended inputs o Two independent integrated analog comparators o One I2C module o One PWM generator block - One 16-bit counter - Two comparators - Produces two independent PWM signals - One dead-band generator o 0 to 43 GPIOs, depending on user configuration o On-chip low drop-out (LDO) voltage regulator

GPIO Usage

PIN SIGNAL Function

---

L3 PA0/U0RX UART0 receive M3 PA1/U0TX UART0 transmit E12 PB0/U0CTS UART0 CTS D12 PB1/U0RTS UART0 RTS L5 PA4/SPIRX SPI receive (pin hardwired to U1RX) M5 PA5/SPITX SPI transmit (pin hardwired to U1TX) H2 PD2/U1RX UART1 receive H1 PD3/U1TX UART1 transmit L4 PA3/U1CTS/SPICLK UART1 CTS or SPI clock M4 PA2/U1RTS/SPISEL UART1 RTS or SPI slave select J11 PF0/LED1 Ethernet LED1 (green) J12 PF1/LED0 Ethernet LED0 (yellow) C11 PB2 Transceiver #INVALID C12 PB3 Transceiver #ENABLE A6 PB4 Transceiver ON B7 PB5 Transceiver #OFF

Stellaris MDL-S2E Reference Design Configuration Options ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^

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

   CONFIG_ARCH=arm

CONFIG_ARCH_family - For use in C code:

   CONFIG_ARCH_ARM=y

CONFIG_ARCH_architecture - For use in C code:

   CONFIG_ARCH_CORTEXM3=y

CONFIG_ARCH_CHIP - Identifies the arch/*/chip subdirectory

   CONFIG_ARCH_CHIP=lm

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

   CONFIG_ARCH_CHIP_LM3S6432

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

   CONFIG_ARCH_BOARD=lm3s6432-s2e (for the Stellaris MDL-S2E Reference Design)

CONFIG_ARCH_BOARD_name - For use in C code

   CONFIG_ARCH_BOARD_LM3S6432S2E

CONFIG_ARCH_LOOPSPERMSEC - As supplied, calibrated for correct operation
   of delay loops assuming 50MHz CPU frequency.

CONFIG_ENDIAN_BIG - define if big endian (default is little
   endian)

CONFIG_RAM_SIZE - Describes the installed DRAM (SRAM in this case):

   CONFIG_RAM_SIZE=0x00010000 (64Kb)

CONFIG_RAM_START - The start address of installed DRAM

   CONFIG_RAM_START=0x20000000

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.

There are configurations for disabling support for interrupts GPIO ports. GPIOH and GPIOJ must be disabled because they do not exist on the LM3S6432. Additional interrupt support can be disabled if desired to reduce memory footprint - GPIOs C-G are not pinned out on the MDL-S2E board.

CONFIG_TIVA_GPIOA_IRQS=y
CONFIG_TIVA_GPIOB_IRQS=y
CONFIG_TIVA_GPIOC_IRQS=n << Always
CONFIG_TIVA_GPIOD_IRQS=n << Always
CONFIG_TIVA_GPIOE_IRQS=n << Always
CONFIG_TIVA_GPIOF_IRQS=n << Always
CONFIG_TIVA_GPIOG_IRQS=n << Always
CONFIG_TIVA_GPIOH_IRQS=n << Always
CONFIG_TIVA_GPIOJ_IRQS=n << Always

LM3S6432 specific device driver settings

CONFIG_UARTn_DISABLE
   The TX and RX pins for UART1 share I/O pins with the TX and RX pins
   for SSI0.  To avoid conflicts, only one of SSI0 and UART1 should
   be enabled in a configuration.
CONFIG_UARTn_SERIAL_CONSOLE - selects the UARTn for the
   console and ttys0 (default is UART1).
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

CONFIG_TIVA_SSI0 - Select to enable support for SSI0
  The TX and RX pins for SSI0 share I/O pins with the TX and RX pins
  for UART1.  To avoid conflicts, only one of SSI0 and UART1 should
  be enabled in a configuration.
CONFIG_TIVA_SSI1 - Select to enable support for SSI1
  Note that the LM3S6432 only has one SSI, so SSI1 should always be
  disabled.
CONFIG_SSI_POLLWAIT - Select to disable interrupt driven SSI support.
  Poll-waiting is recommended if the interrupt rate would be to
  high in the interrupt driven case.
CONFIG_SSI_TXLIMIT - Write this many words to the Tx FIFO before
  emptying the Rx FIFO.  If the SPI frequency is high and this
  value is large, then larger values of this setting may cause
  Rx FIFO overrun errors.  Default: half of the Tx FIFO size (4).

CONFIG_TIVA_ETHERNET - This must be set (along with CONFIG_NET)
  to build the Stellaris Ethernet driver
CONFIG_TIVA_ETHLEDS - Enable to use Ethernet LEDs on the board.
CONFIG_TIVA_BOARDMAC - This should be set in order to use the
  MAC address configured in the flash USER registers.
CONFIG_TIVA_ETHHDUPLEX - Set to force half duplex operation
CONFIG_TIVA_ETHNOAUTOCRC - Set to suppress auto-CRC generation
CONFIG_TIVA_ETHNOPAD - Set to suppress Tx padding
CONFIG_TIVA_MULTICAST - Set to enable multicast frames
CONFIG_TIVA_PROMISCUOUS - Set to enable promiscuous mode
CONFIG_TIVA_BADCRC - Set to enable bad CRC rejection.
CONFIG_TIVA_DUMPPACKET - Dump each packet received/sent to the console.

Configurations ^^^^^^^^^^^^^^

Each Stellaris MDL-S2E Reference Design configuration is maintained in a sub-directory and can be selected as follow:

tools/configure.sh lm3s6432-s2e:<subdir>

Where <subdir> is one of the following:

nsh: Configures the NuttShell (nsh) located at examples/nsh. The Configuration enables both the serial and telnetd NSH interfaces.

NOTE: As it is configured now, you MUST have a network connected.
Otherwise, the NSH prompt will not come up because the Ethernet
driver is waiting for the network to come up.  That is probably
a bug in the Ethernet driver behavior!