LPC17 specifications

MIDIbox HUIs
1

Hello !

I’ve been lurking here around for a while, before asking questions…( occasionally since 2008, but I felt never ready enough to start some projects ). I think now is the right moment to move on :wink:

I’m Roman from Germany and have some background in electronics ( …my education was a around 10 years ago ). I’m actually programming in Max/MSP/M4L, mainly for Monome and Lemur devices. I’m primarily interested in building a Controller that commuticates over OSC with software like Ableton Live ( LiveAPI / Python ), Max/MSP and the like.

I think before I go too much into details with my project I have to extend my skillset first. ( learning some C/Python code, dive into electronics again e.g.) This will take a while and in the meantime I decided to study the midibox platform…

So I have some questions related to LPC17 Core:

1: can someone point me to te datasheet where I can look into DIN/DOUT, AIN/AOUT specifications, I simply can’t find this information on the frontpage/forum.

2: is it possible to cascade multiple cores, in order to have more A/D inputs/outputs ?

any help is appreciated…

thanks, Roman

2

Hi, In general AIN/AOUT DIN/DOUT is achieved with external modules, these are daisy-chained to achieve large numbers of inputs/outputs using shift registers.

Take a look at http://www.ucapps.de under the MB Hardware Platform you will see the different modules that can be connected to the core module.

Cheers

Phil

3

Hi, In general AIN/AOUT DIN/DOUT is achieved with external modules, these are daisy-chained to achieve large numbers of inputs/outputs using shift registers.

Take a look at http://www.ucapps.de under the MB Hardware Platform you will see the different modules that can be connected to the core module.

Cheers

Phil

16 shift redisters for din and dout =128 inputs and outputs

64 analog inputs via ain

4

16 shift redisters for din and dout =128 inputs and outputs

64 analog inputs via ain

I purposely didn’t quote a number as they are the defaults but by no means are they limits! I know that people have successfully tested 32 DIN shift registers. If some method of ‘boosting’ the SPI signal was used then (in theory) many more DIN/DOUT modules could be supported (with minor code changes)

5

Thanks guys !

I found the schematic here: http://ucapps.de/mbhp/mbhp_core_lpc17.pdf

After some researching I came up with this specs:

LPC 17 Core I/O:

  • 4 x DINX4 = 128 ins

  • 4 x DOUTX4 = 128 outs

  • 2 x AIN = 64 ins

  • 2 x MIDI In/Out

  • 1 x USB

  • 1 x Ethernet

  • 1 x SD Card

  • 1 x 2X20 LCD

There is also an unused, mysterious J10 Jack on the board, labeled as “General Purpose IO Portâ€. What can it be used for ? And what is a scan matrix ? ( there is a mention in documentation about 16 (8x8) scan-matrices…)

Are these specs correct so far ? Please correct me, if I’m wrong.

thanks,

Roman

6

Finally I documented all available ports at the MBHP_CORE_LPC17 page.

(press the refresh button of your webbrowser if you don’t see the update)

The purpose(s) of J10 are described there as well.

And I gave you access to the Programmers Lounge, where you will find the full history/discussions/background informations/preliminary projects/etc. :wink:

Best Regards, Thorsten.

7

That’s great !

And Programmers Lounge looks so promising… there is a lot to explore.

Huge thanks !!!

8

Did i got that right, that daisy chaining 8 DIN modules does not need additional hardware, only software tweeking?

Would be too great for me…

Thanks

9

Did i got that right, that daisy chaining 8 DIN modules does not need additional hardware, only software tweeking?

Would be too great for me…

For 8 DINX4 modules you would have to enter following definition to the mios32_config.h file of the application:

// scan 8 DINX4 modules
#define MIOS32_SRIO_NUM_SR 32
[/code]









thats all...







Hardwarewise it could work without additional hardware if the cables between DINX4 modules is as short as possible.



It's also very important that they are connected in a long chain! Don't use starlike wiring, this could result into uncontrollable impedance issues.



If SCLK/RCLK should get unstable, the chain has to be terminated with a 100 Ohm/ 100 pF RC (see this schematic as example: [http://www.ucapps.de/midibox\_seq/mbseq\_v4\_din.pdf](http://www.ucapps.de/midibox_seq/mbseq_v4_din.pdf))







Best Regards, Thorsten.