Building a Maple Mini from scratch. What to do with a blank STM32F103CBT6?

LeafLabs Garden » Support » Maple Hardware Support

Building a Maple Mini from scratch. What to do with a blank STM32F103CBT6?

(8 posts) (3 voices)

Started 4 years ago by DDDD
Latest reply from siy

DDDD
Member

I am coming from the Arduino community where for several projects I built my own custom Arduino pcb (so I could easily duplicate them for things like larger lighting or sound projects). First of all pcbs could be 2 layer (easy to deal with) and I had a choice of DIP or SMT processor. I usually used smt and was comfortable soldering them.

Once I had a board made and a blank uController IC all I had to do was power it up and then burn the Arduino bootloader using and avrispmkii (which would automatically set the right fuse settings) and then burn any code to it using the avrispmkii as well.

The STM32F103CBT6 on the Maple mini is not as fine pitch as the Maple Native or other boards and is similar to the arduino. To me this is an attactive IC to work with as a start and would be a good transition.

What I am not clear on so far is what state is a blank STM32F103CBT6 in? What physical tools do I need to have in order to get it to work with the Maple IDE? JTAG?

Or if I built a pcb identical to the Maple Mini (used the open source files) would it just "work"?

Posted 4 years ago #
siy
Member

STM32F103 controllers have one feature which makes them very convenient for bootstrapping - built-in hardware (i.e. it does not depend on bootloader) serial programmer (and I guess other families have it too). In order to use it you need serial port with TTL signal levels (USB-Serial converters, probably, most convenient for this purpose). Details of flashing bootloader can be found here: http://leaflabs.com/docs/bootloader.html. I'd suggest to try use stm32flash utility (can be found here http://code.google.com/p/stm32flash/) instead of stm32loader.py since it worked much better for me (just in case: I'm not the author of this utility), but your mileage may vary.

Posted 4 years ago #
gbulmer
Moderator

To be pedantic, the STM32's have a manufactured-in bootloader program which can load from one or more (depending on the STM32 family) peripheral interfaces.

AFAIK all STM32 bootloaders will load from a USART, and some will load over USB, CAN, Ethernet and even wireless (802.15.4).

I use an FTDI USB to 3.3V TTL serial cable and the Python program to upload from a Mac to the manufactured in STM32F103 bootloader. I had to upgrade the version of Python than comes pre-installed with Mac OS X, but then it worked fine.

If you are happy working this way, you don't need to put any other bootloader on the STM32F. Just upload your application.

Another possibility is In-Circuit Programming over JTAG or Serial Wire Debug (SWD), using ST Micro's STLINK/V2:
http://www.st.com/internet/evalboard/product/251168.jsp
Again this doesn't require any software to be uploaded except your application.

This is about $25, and not only supports upload, it also supports 'proper' hardware debug, giving breakpoints, single stepping programs, inspecting registers, changing flash memory, etc.

ST put a version version of STLINK/V2 on their STM32F4-DISCOVERY development board:
http://www.st.com/internet/evalboard/product/251168.jsp
which has a STM32F4 MCU, and an STLINK/V2. It is not as convenient to use as an uploader/debugger as the STLINK/V2, but it is even cheaper:
http://www2.mouser.com/ProductDetail/STMicroelectronics/STM32F4DISCOVERY/?qs=J2qbEwLrpCGdWLY96ibNeQ%3d%3d
at about $18

To use the STLINK/V2, you'll need some software. ST provide some for free on Windows.
Lots of development environments support it, and I believe OpenOCD is close to supporting it for hardware debugging.

I have started experimenting with stlinkv2-util http://code.google.com/p/arm-utilities/wiki/STLinkDownload
which is Open Source. It is by Becker and his colleagues. It looks like a very, very useful piece of software.

Posted 4 years ago #
DDDD
Member

ok this is great. So now what I would like to do is build a board that basically has a the guts of a mini, 1mb of ram (like the Native) and WM8731 codec (like the audiocodecshield).

This would be a very useful platform for me to do some dsp audio experiments.

Posted 3 years ago #
gbulmer
Moderator

DDDD - must it be the 48pin part, the same as on a Maple mini?

That 48pin part does not have a fast memory interface to RAM, you'd need to use SPI or I2C. They don't have I2S, so it would be more awkward to talk to codec's.

AFAIK, the smallest part package with an external memory interface is 100pins.
The smallest part package with I2S is 64pin.

You might want to consider 64pin parts.
They don't have external memory interfaces, but the higher family parts have dual DAC's, which might be useful to experiment with.

Posted 3 years ago #
DDDD
Member

The only reason for sticking with the maple mini part is that afaik that package is a little easier to hand solder than the finer pitch of the larger pin count parts.

As I read through the details of the Maple Native more I realised that part of the reason for the addition of the 1mb memory was the fact that there were many more pins available to communicate with the SRAM.

So it sounds like if I want codecs and memory I really need to stick with the Maple Native format.

I do all my development on a Mac and I use Eagle for all schematic/pcb capture. I have another thread going on this but it would be nice if the Maple schematics/boards stayed in Eagle format as well. Kicad is only experimental on mac platform unfortunately.

Posted 3 years ago #
gbulmer
Moderator

DDDD -

The only reason for sticking with the maple mini part is that afaik that package is a little easier to hand solder than the finer pitch of the larger pin count parts.

The pitch (e) of LQFP48, LQFP64, LQFP100, and LQFP144 are all the same at 0.5mm, none are finer pitch than others. I agree it is easier to solder fewer pins :-)

I2S for the codec is available on all 64pin high-density STM32F103 parts, upwards.

IIRC, LQFP100 parts have restricted memory interfaces, so you might be looking at LQFP144.

I also do (most of) my development on Mac, and use Eagle.

Posted 3 years ago #
siy
Member

LQFP-48 has 0.5mm pitch just like 64-, 100- and 144-pin LQFP packages. Hand soldering of 48 and 64 pin packages is about the same by the means of complexity if PCB has solder mask. Otherwise 64-pin package is a bit more complex for manual soldering.

Posted 3 years ago #

RSS feed for this topic

Reply

You must log in to post.