The Cortino is a complete development system for the 32-bit ARM Cortex M3 Microprocessor. In the popular Arduino format and pinout. From only $39.99.

The Cortino is USB powered and it connects to the PC at 3Mbit/s via USB. Software is included to reflash the Cortino via the USB link (ISP). So all you need to get started on ARM Cortex development is a Cortino, a USB cable, and a compiler.

Key Features

• MCU: STM32 32-bit ARM Cortex with 32KByte to 512KByte Program Flash, 6KByte to 64KByte RAM, up to five USARTs, three SPI, two I2C, six 16-bit timer/counters, three multi-input 12bit ADCs, one 2-channel 12bit DAC. Multi-channel DMA controller. Two watchdogs. 5V tolerant I/O. Up to 72MHz operation
• Built-in debug via the USB interface, plus ARM 2x10 pin JTAG connector
• Two LEDs plus a power supply LED
• User reset button
• On board voltage regulator 3.3V with up to 200mA current
• USB 5V available on the expansion connectors
• Multiple expansion headers, as on the Arduino
• Reset circuit, software operated via the USB interface, or by the reset switch, or via an expansion connector
• Dimensions: 2.1x2.7" (53x68mm)

What We Changed

The Arduino is based on the splendid Atmel ATmega168 processor, a modern 8-bit AVR RISC core running at 10MHz with 16KB of Flash and 1KB of RAM. The Cortino is based on ARM's latest 32-bit Cortex M3 RISC core, running at 72MHz with 512KB of Flash, 64KB of RAM, and a powerful DMA controller. Obviously we changed a few things...

But we tried to change only what had to be changed. The headers are the same size and in the same places, the board is the same size, with the same mounting holes, and it can be USB-powered or stand-alone. Here's a summary of the changes, but you will need to look at the header pinout documentation here to get the details.

1. The board is 100% surface-mount. Modern processors, particularly in 64-pin packages, are simply not made in through-hole packages.
2. In system programming is via the USB connection, so the ISP connector is unused.
3. The on-board LEDs are driven via buffers, so the signals that drive them have minimal load.
4. The traditional digital I/Os have been duplicated on a 100mil grid for easier prototyping
5. JTAG debugging is widely used in the 32-bit world. We implement zero-cost JTAG debugging via the USB connection (health warning - this software is under development but not yet shipping). The Cortino also implements a full 20-pin JTAG debugger footprint, compatible with the numerous JTAG debuggers out there.
6. The micro can communicate with the PC via its USART and the USB chip at speeds up to 3Mbit/s.

Like Father, Like Son...

A Cortino board is on the left, an Arduino on the right - we used the same format.

Options

The Cortino features an ARM STM32 Cortex M3 microcontroller in a 64-pin package. Right now ST Micro offer 18 variants of this chip/package combination in three product families. The STM32F103 parts operate at 72MHz with up to 512KB of ROM and 64KB of RAM. The STM32F102 parts operate at 48MHz with up to 128KB of ROM and 16KB of RAM. And the STM32F101 parts operate at 36MHz with up to 512KB of ROM and 48KB of RAM. The three families are summarised here.

We have chosen to offer the Cortino in three standard variants.

Two variants have STM32F103 chips installed and are very similar except for the memory size. The first has 512KB of Flash and 64KB of SRAM, the second has 128KB of Flash and 20KB of SRAM. Both variants are fully-populated boards with all features installed.

The third variant is and entry-level model which omits the power connector and the associated voltage regulator, the reset switch, and the oscillator crystal. This means that it is USB-only, not stand-alone, and it runs from the built-in calibrated oscillator. An STM32F101R6 processor is fitted, with a maximum clock rate of 36MHz.

In summary, the three variants are:

• Cortino3RE, with a 72MHz STM32F103RE - 512KB Flash ROM and 64KB RAM
• Cortino3RB, with a 72MHz STM32F103RB - 128KB Flash ROM and 20KB RAM
• Cortino1R6, with a 36MHz STM32F101R6 - 32KB Flash ROM and 6KB RAM, USB only

The Cortino1R6 is only $39.99, which is approximately 32 Euro or 27 British Pounds.

Note: at the moment the Cortino is primarily an OEM product. This means that batches are built to meet OEM orders, with one-off orders being supplied from overbuilds. Please contact us (sales@bugblat.com) to check the stock position before placing an order.

• Cortino3RE, including software $69.99 Add to Cart
• Cortino3RB, including software $59.99 Add to Cart
• Cortino1R6, including software $39.99 Add to Cart

It may make sense to order multiple units. Every vendor says that, but it is true. Shipping cost is constant and buying multiple units cuts down the per-unit cost. And substantial discounts are available for bulk purchases.

Documents

• Cortino header pin assignments
• Cortino schematic

Getting Started with the Cortino

1. Download and run the corins.exe software installer.
2. Plug in the Cortino module. When this is done for the first time it immediately causes the operating system to prompt you for the location of the necessary USB drivers. The installer will have placed these in the drivers subdirectory of your Cortino application directory.
3. Cortino modules are delivered with a simple application programmed into the Cortex M3 memory and the LEDs on the board should start flashing.
4. Run the corinfo application to verify the installation. The installer will have left shortcuts on your desktop and in your Start menu.

The release_notes.txt file in the installation directory has more information on the utilities and sample programs supplied with the Cortino.

Drivers

The Cortino uses a USB interface chip manufactured by FTDI Ltd www.ftdichip.com. Our example software accesses the hardware via drivers provided by FTDI - we use the FTDI D2XX family of drivers. Drivers are included in the installation package, and the most recent drivers are available via the FTDI web site here.

32-bit and 64-bit Windows XP and Windows Vista drivers are packaged up with a CDM prefix - for example, CDM_2.0.0.zip or CDM_2.0.0_x64.zip.

Windows 98 and Windows ME drivers are packaged up with a D prefix - for example, D30104.zip.

The FTDI USB chip on the Cortino is programmed with the default ID codes. These are the default Vendor ID (VID) and the default Product ID (PID), compatible with standard drivers for this chip.

Tool Chains

There are many tool chains for the ARM Cortex processor. Some of the most prominent Windows solutions are listed below, but a web search will find others for Windows and for Linux. The basic distinction is between tool chains based on GCC (the open source GNU Compiler Collection) and proprietary tool chains. Tool chains based on proprietary compilers are generally thought to produce somewhat more compact code; tool chains based on GCC are noticeably less expensive.

• The low cost Rowley tool chain for the ARM Cortex has a good reputation. It is based on GCC and sold as the CrossWorks product. All licenses are unlimited in code size. A 30-day Evaluation license is free, and there are low cost Personal and Educational licenses, plus a Commercial license. CrossWorks is particularly easy to set up. www.rowley.co.uk


• As they say on their web site, "CodeSourcery works with ARM to develop improvements to the GNU Toolchain for ARM processors and provides regular, validated releases of the GNU Toolchain." The Sorcery G++ product, unlimited in code size, comes in the free command-line Lite edition, plus the inexpensive Personal edition and the full Professional edition. www.codesourcery.com


• The Raisonance tool chain for the ARM Cortex is also based on GCC. It is sold as the RKit-ARM product and optionally includes a relatively inexpensive hardware debugger. The standard package is free and includes the Ride7 environment plus unlimited versions of the GCC tools. www.raisonance.com


• Keil is an ARM subsidiary and has a very well respected ARM Cortex compiler, sold as the RealView MDK product line. They offer an evaluation version of MDK, limited to 32KB of code, a Basic version, limited to 256KB of code, and a Standard unlimited version. The Basic and Standard versions are somewhat expensive for the typical hobbyist. www.keil.com


• IAR also has a fine Cortex compiler. They offer a free Kickstart edition, limited to 32KB of code, an unlimited 30-day Evaluation edition, a Baseline edition, limited to 256K of code, a Limited edition, and a Standard edition. The Baseline, Limited, and Standard editions are not aimed at the typical hobbyist. www.iar.com

Resources

Information sources on the ARM Cortex and the STM32 micro include these:

• The low density STM32F101x6 data sheet
• The medium density STM32F103xB data sheet
• The high density STM32F103xE data sheet
• The STM32 reference manual
• The Insider's Guide to the STM32 ARM based Microcontroller (Hitex)
• The ST Micro STM32 site
• The very well written ARM Introduction to the Cortex M3
• The ARM site (www.arm.com) has full documentation here on the ARM Cortex-M3 processor core, including the ARM Cortex M3 Technical Reference Manual

Please note that the Cortino is technical development equipment. It is designed for users who are familiar with electronic design and debugging, and familiar with the usual safety precautions when working with electronic equipment.