MMA955XL development recommendations

[pholm]

I'm interested in replacing a PIC16LF1823 and MMA8452 combination with the MMA955XL device, to save BOM cost and board area. 

However, it uses the very old Coldfire V1 core, and it is very hard to find information about what software and hardware is required to develop for this device.  Is the MMA955XL in active production, or has it been deprecated?  What is the minimum required programming device and SDK to compile a custom firmware into your KITMMA955XLEVM evaluation board?

Also, what is the supply current below 1.5V?  Although the MMA8453 is rated at ~1uA minimum power, it actually draws 15,000 uA at around 1.4V, due to some undocumented silicon short circuit effect.  This makes it unsuitable for battery powered operation.  Does the MMA955XL behave similarly?

[margaretnadworn]

Hi, Peter,

Your email has been forwarded to an Apps Engineer to ensure that all of your questions are answered properly.  My response should be able to get you started in the interim.

The MMA955xL represents a family of devices.  The whole family is in active production.  The parts are preloaded with firmware at the factory.  This means that it is important to identify the right component to put on the board.

The MMA9550L and the KITMMA9550LEVM contain a baseboard with a daughtercard containing the MMA9550L.  Similarly the MMA9551L/KITMMA9551LEVM contains the same hardware but the firmware has a different set of features.

For a complete description of the various members of the family, please review the Data Sheet which can be downloaded from the freescale.com web site and search for KITMMA955XLEVM.  Once there, the Data Sheet  is available under the Documentation tab.  In the documentation section, Quick Start Guides, User Guides are also available.

The Software for these two boards is described in the Software Reference Manual - MMA955XLSWRM also available under the Documentation tab for the board.  In the same location, you will see an App note, Building Custom Applications on the MMA9550L/MMA9551L, AN4129.

The MMA9553L is a variant of the MMA9553L with a pedometer application.  There is very little memory available for addtitional programming capabilities.

This family of devices is not currently supported by ISF but it is on the ISF roadmap for the second half of the year.

My apologies for not responding to all aspects of your question.    I hope you have enough to move forward for now.

Regards,

Margaret

[pholm]

Hi Margaret,

Thanks for the clarification.  I guess this family is not a suitable replacement for a general purpose MCU+discrete accelerometer. 

Peter

[JackITB]

Hi Peter,

Let me give you some more details:

1/ information about what software and hardware is required to develop for this device:

- recommended IDE is "CodeWarrior Development Suite" v10.6

You can  use the Special Edition which is free of charge http://www.freescale.com/webapp/sps/site/overview.jsp?code=CW_SPECIALEDITIONS

It has a limitation regarding code size (e.g. 64kB for CFV1 and 128kB for Kinetis) but that's more than enough for MMA955xL Firmware development. Simply download the Eclipse version, either online or offline

Special Edition: CodeWarrior for Microcontrollers 10.6  (Eclipse, Online)

- in term of hardware, you as well as Margaret mentionned KITMMA955XLEVM. I will also add the Accelerometer Kube Demo|Freescale which is the demokit for MMA9559L version.

- in order to help you get up to speed with code development, refer to AN4129 and its associated CodeWarrior project archive AN4129SW.zip for MMA9550/MMA9551, where as CodeWarrior project of MMA9559LKUBE demo will provide a complete MMA9559 project example.

2/ what is the supply current below 1.5V?

When you do a ramp on the supply voltage, max current is about 1-2mA (in the 1.5-1.7V range) and a few µA elsewhere, so you should have no issue at all in a battery powered application

3/ this family is not a suitable replacement for a general purpose MCU+discrete accelerometer

I would disagree with your conclusion here. Indeed MMA955xL offers in a small form factor at the same time a high performance 3-axis accelerometer (up to 16 bits resolution, up to 3906Hz sampling frequency, very low noise) and an effective 32bits MCU with Flash/RAM/ROM and standard features such as I2C/SPI, timer, GPIO, PWM...

There are 3 flavors of the family that can be of interest for you: MMA9550/9551/9559. Last version is loaded with a lightweight infrastructure so you have lots of flexibility and memory space to implement your own data processing and custom algorithm. In the first 2 versions, we provide a bunch of features and fonctions that you can simply exercise to speed your development. You can take a look at their Software Reference manuals for details (MMA9559LSWRM and MMA955XLSWRM respectively).

Regards,     Jacques.

[pholm]

Hi Jacques,

Thanks for the clarification.  It sounds like the MMA9559 is what I was looking for.  I'll read up on it in more detail.  Can you clarify what the recommended in circuit debugger tool is for this device?

Regards,
Peter

[JackITB]

Hi Peter,

Your right, I forgot to mentioned the need for a USB/BDM Multilink hardware from P&Emicro (MCU programming and debug interface). USB-ML-12 is their entry model (at $99) for CFV1, but you can select a more powerful and versatile model (compatible also with our Kinetis MCU) such as USB-ML-UNIVERSAL or USB-ML-UNIVERSAL-FX.

Regards,     Jacques.

PS: I'd like to point out that the 15mA current surge at low voltage reported on MMA8453Q was actually a mistake and this device simply draws about 2mA max during Vsupply ramp-up. In any case, a fast rise time of the supply voltage is preferable to reduce the duration of the leak.

[margaretnadworn]

Peter,

I'm sorry if I said something that led you to that conclusion which is not quite a fair representation.  It is a ColdFire with an accelerometer.  The other alternative is using ISF 1.1 on the FXLC95000.

I've nudged the apps engineers one more time.

Thank you,

Margaret