NetBurner’s MOD5213 (see Fig. 1) is based on a Freescale MCF5213 32-bit Coldfire microcontroller (see Fig. 2). The microcontroller is at home on a small PCB that plugs into a standard 40-pin DIP socket. An on-board oscillator and voltage regulator means a developer need only supply the basic power requirements and any necessary connectors on a host board to take advantage of the MCF513. This is the case with Netburner’s development board (see Fig. 3), which is included with the development kit. One thing I would like to have seen is a set of insulated feet on the bottom of the development board.
The MCF5213 houses a V2 Coldfire core that runs at 66 MHz. The core includes hardware multiply/accumulate and division support. It has 256 kbytes of flash that starts out with a copy of the µC/OS operating system. The small OS leaves the majority of space for application code. There is 32 kbytes of on-chip SRAM, so your application will need to stay within these limits. Off-chip memory is not an option unless you implement a serial or flash interface using the undedicated I/O pins.
The microcontroller has built-in JTAG that is accessible via the version of the MOD5213 with a small edge connection at one end of the board. This is the case with the development kit reviewed here. A version of the module is available without these pins. That version is more suitable for production environments.
The peripheral complement is very nice for embedded applications. It includes:
CAN 2.0B controller with 16 message buffers
Three UARTs with DMA capability
Queued serial peripheral interface (QSPI)
I2C controller
Four 32-bit timer channels with DMA capability
Four 16-bit timer channels with capture/compare/PWM
4-channel 16-bit or 8-channel 8-bit PWM generator
Two periodic interrupt timers
4-channel DMA controller
8-channel 12-bit ADC
Up to 33 general-purpose I/O (GPIO shared with other peripherals)
The GPIO are 3.3-V ports so don’t connect them to a 5-V TTL device. Fried transistors are not a developer’s choice of food. The on-board voltage regulator will handle anything from 4.5V to 7 V DC. An external power supply is included for the development board, and there are screw terminals available for power connections as well. Two of the serial ports are connected to an RS-232 driver/receiver chip on the development board before being connected to the 9-pin connectors. You will have to provide your own drivers and connectors if you intend to use the CAN support.
Soft Burn
Netburner uses the uC/OS operating system on most of its products, including the MOD5270 I reviewed earlier (see “Getting On The Network: Fast” ED Online ID 10580). The Windows-based NNDK (Netburner Network Development Kit) software and IDE (see Fig. 4) is the same as well. The NNDK uses Cygwin to host the GNU development tools. Cygwin can get a little cranky if you need to set up multiple target platforms, but mixing Netburner’s installations is relatively easy as long as you use the latest version for each platform.