Keil Evaluation Kits for ST Microelectronics Cortex M3 parts  

Keil currently sells various versions of their microcontroller evaluation kits. For example, consider the kits for the ST Microcontroller Cortex M3 part. There are two version of the STM32 kit now shipping with a third version due to ship in December 2009 for the so-called Connectivity series of parts. The versions currently shipping are known as MCBSTM32 and MCBSTM32E.

The MCBSTM32U ships in two versions, the MCBSTM32U and the MCBSTM32UME. The MCBSTM32E ships in two versions as well, MCBSTM32EU and MCBSTM32EUME.

Suffice to say, this generates confusion in the user’s mind. Lets sort this out by looking at the kits.

The MCBSTM32 was the first kit for the ST Microcontroller Cortex M3 part. The key specifications for the board are:

Processor: STM32F103RB is an ARM 32-bit Cortex-M3 Microcontroller, 72MHz, 128kB Flash, 20kB SRAM

I/O: 1 Serial Port, 1 CAN Port, 1 USB Device Port, 16×2 Character Display, 3 Pushbuttons, 8 LEDs

The MCBSTM32 Photo:

The specifications page for the board contains further details at: http://www.keil.com/arm/mcbstm32/specs.asp

The MCBSTM32U means that you get a ULINK-2 debugger with the kit. This is Keil’s most capable and flexible debugger, and is pictured here:

The MCBSTM32UME means that you get a ULINK-ME debugger with the kit. The ULINK-ME debugger is only available with kits, and cannot be purchased as a stand alone item. Despite its seemingly spare appearance, it is a perfectly capable debugger, and does almost everything that the ULINK-2 can do. Its main limitation is that it can only connect to standard 20-pin JTAG connectors. A nice thing about ULINK-ME is that it can power the MCBSTM32 board, so you do not need a separate power supply.

 The ULINK-ME requires a Mini Type B 4 position USB plug, whereas the ULINK-2 uses a more conventional Type B 4 position plug.

The major advantage of ULINK-ME is cost. Kits with ULINK-ME are $100.00 less than kits with ULINK-2. 

The MCBSTM32E follows a similar nomenclature format: When a “U” is appended to the designation, it means a kit with a ULINK-2 debugger, and when a “UME” is appended, it means a kit with a ULINK-ME debugger.

Here is a photo of the MCBSTM32E board:

There are two key differences between the MCBSTM32E and the MCBSTM32:

Processor: STMicroelectronics STM32F103ZE is an ARM 32-bit Cortex-M3 Microcontroller, 72MHz, 512kB Flash, 64kB SRAM. Note the increase ROM and RAM resources. Using this board means you have a lot more flexibility in trying out RTOSes, communication protocol stacks and other middleware. 

I/O: note that you have a ¼ VGA screen, which gives you more flexibility than the 16×2 character display. See full specs here: http://www.keil.com/arm/mcbstm32e/specs.asp

Mark’s recommendation: 

When in doubt, get the evaluation board with the most memory resources. The small incremental cost may be well worth it down the road when you need more ROM or RAM to play with.