Description

This package provides the hardware design HAL for the version 8.0 appselector hardware design running on a Nios II Embedded Evaluation Kit, Cyclone III edition, also known as the NEEK board. This is the hardware design programmed into boards as shipped from the factory, and in the examples/application_selector and factory_recovery directories of the software supplied with the board.

	Note
	There are a number of different and incompatible versions of the appselector hardware design. This package supports only the 8.0 version, a copy of which is supplied with eCosPro releases. If your NEEK board runs a different version of the hardware design then it will be necessary to update the board before eCos can be used. Instructions on how to do this are given below.

The hardware design includes the following functionality:

Setting up a Board

The eCos port targets a VHDL hardware design named appselector. This hardware design is provided by Altera, and new NEEK boards usually come with this h/w design preprogrammed into the external flash. However, there are several different and incompatible versions of this design. The eCos port specifically targets the 8.0 version. If your board comes with a different version of the h/w design or if a different h/w design has been programmed into flash then it will first be necessary to program the right design into flash. The required image file restore_cycloneIII_3c25.flash can be found in the nios2/ subdirectory of the installation. The sources for this h/w design are also included with the release.

The most convenient way to install a h/w design is to use Altera's flash programming tools, provided with Quartus and the Nios II Embedded Development Suite (nios2eds). The NEEK board has a built-in jtag interface accessible via a USB port, which can be used for this purpose.

The Quartus tools can be downloaded from Altera. Version 13.1 is the last version released that supports the Cyclone III FPGA that the Neek board is based upon. The free “web” version can be downloaded from http://dl.altera.com/13.1/?edition=web and the subscription version from http://dl.altera.com/13.1/?edition=subscription. Version 13.1, unlike some earlier versions, incorporates the EDS tools within the Quartus download.

Assuming that the Altera software as been correctly installed and that a USB cable has been connected between the host PC and the NEEK board, the following commands will install Altera's appselector application and support data, as well as the hardware design. On a Windows PC these commands need to be issued within the Altera EDS Nios command shell, not the Windows or eCos command shells.

$ cd <ecosproinstalldir>/ecos-<version>/nios2
$ nios2-flash-programmer --base=0x04000000 --go restore_cycloneIII_3c25.flash

If application development will use just the jtag interface then the board can now be used to run eCos applications configured for RAMJTAG startup. This involves running the Nios II gdb server supplied by Altera:

$ nios2-gdb-server --tcpport 9000 --tcppersist

eCos applications and tests configured for RAMJTAG startup can now be downloaded and executed via nios2-elf-gdb at another command line prompt. For example:

nios2-elf-gdb <executable-file>
(gdb) target remote localhost:9000
(gdb) set $ienable=0
(gdb) load
(gdb) continue

When using jtag, by default diagnostic output will be directed to the serial port and may be viewed using a terminal emulator configured for 115200/8N1 with no handshaking.

If instead application development will happen via RedBoot then the next step is to install a RedBoot image, replacing the appselector application. Note you must power cycle the board between the above step and this one. Start by connecting a serial cable between the host PC and the NEEK board, and start up a terminal emulator running at 115200/8N1 with no handshaking. Next use Altera's EDS command shell to issue the following commands to program the RedBoot image into flash via jtag:

$ cd <ecosproinstalldir>/ecos-<version>/loaders/nios2_neek_cyclone3_appselector
$ bin2flash --location=0x00100000 \
          --input=redboot_ROM.bin \
          --output=redboot.flash
$ nios2-flash-programmer --base=0x04000000 \
                       --sidp=0x08002f40 \
                       --id=1727563914 \
                       --no-keep-nearby \
                       --go \
                       redboot.flash

The --sidp and --id arguments are used to check that the board is running the correct h/w design. The --go argument causes the board to restart, so RedBoot should now be running and should have output its banner and a prompt. The terminal emulator can now be used to execute the following commands at the RedBoot prompt to initialise the Flash contents:

RedBoot> fis init
RedBoot> fconfig -i

eCos applications and tests configured for RAM startup can now be downloaded and executed via nios2-elf-gdb. For example, to run the prebuilt eCos test over serial, first exit the terminal emulator so that nios2-elf-gdb can access the serial port, and then use the following commands:

nios2-elf-gdb <path>/thread_gdb
(gdb) set remotebaud 115200
(gdb) target remote /dev/ttyS0
(gdb) load
(gdb) continue

RedBoot binaries are provided under the 'loaders' directory in the release. They may be rebuilt by making RAM and ROM startup RedBoot images in the documented manner, each in a separate working directory. For RAM startup:

$ ecosconfig new nios2_neek_cyclone3_appselector redboot
$ ecosconfig import <path>/redboot_RAM.ecm
$ ecosconfig check
$ ecosconfig tree
$ make

The .ecm import file can be found in the misc subdirectory of this package. Similarly for ROM startup:

$ ecosconfig new nios2_neek_cyclone3_appselector redboot
$ ecosconfig import <path>/redboot_ROM.ecm
$ ecosconfig check
$ ecosconfig tree
$ make

Configuration Options

This hardware design HAL package will be loaded automatically when creating an eCos configuration for the nios2_neek_cyclone3_appselector target, together with the Nios II architectural HAL CYGPKG_HAL_NIOS2 and the platform HAL CYGPKG_HAL_NIOS2_NEEK_CYCLONE3_BOARD. It should never be necessary to load this package explicitly. Unloading the package should only happen as a side effect of switching target hardware.

Selecting the nios2_neek_cyclone3_appselector target will also load a flash driver, a serial driver, an ethernet driver, and I²C support. The flash driver will be inactive unless the configuration also includes the generic flash support package CYGPKG_IO_FLASH. The serial driver will be inactive unless the configuration includes the generic serial support package CYGPKG_IO_SERIAL and the option CYGPKG_IO_SERIAL_DEVICES is enabled. The ethernet driver will be active only in eCos configurations which involve networking. The I²C package is always active, but any functionality that is not used directly or indirectly will be removed via link-time garbage collection.

The port to the appselector h/w design supports three startup types:

For ROM and RAMJTAG startup, by default the uart will be used for the diagnostics channel. This can be changed via the configuration option CYGIMP_HAL_NIOS2_DIAGNOSTICS_PORT. The alternative destination is discard which just discards all diagnostics output. For RAM startup the application will inherit its diagnostics channel from the RedBoot ROM monitor.

The configuration option CYGNUM_HAL_RTC_PERIOD can be used to change the system clock frequency. The default value gives a 100Hz clock.