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FEZ Domino: Minimum SPI clock?


I am curious if there is a minimum SPI Clock rate on the FEZ Domino. I have been experimenting with Newhaven Displays which apparently want a SPI clock of 100Khz. If I try to run the display with a higher clock rate, it drops characters, but if I try to reduce the clock to 100Khz, I get a System.InvalidOperationException when I try to write to the Display.

            SPI.Configuration spiConfig = new SPI.Configuration((Cpu.Pin)FEZ_Pin.Digital.Di9, false, 0, 0, true, true, 100, SPI.SPI_module.SPI1);
            spiInterface = new SPI(spiConfig);
            spiInterface.Write(data); // exception thrown here.

The slowest clock I can successfully set is 200Khz, but the display drops characters at that speed.


This is one thing we are trying to improve in the release coming shortly.

More details come in few days


Hi, I was wondering if there has been any progress on lowering the clock rate, I’m trying to talk to one of these and it has a minimum clock speed of 125KHz, I’m trying to run at 150Hz (the lowest I can seem to set) but it’s dropping data.




Next SDK is coming out in few days and it will include the low SPI clock rate.


Thanks for the update, I’ll keep an eye out for it.


I’m also interested in low SPI clock. I was happy to find the nbew framework (from April 21th).
Unfortinatly I found that the minimun clock frequnecy ist still around 150kHz.
I also found that the version number of the assemlby is still instead of
Could that be the reason that the new version does not work?





What device are you using and please provide code example.


I’m using FEZ Panda II board. The code I use is the following:

using System;
using System.Threading;

using Microsoft.SPOT;
using Microsoft.SPOT.Hardware;

using GHIElectronics.NETMF.FEZ;

namespace FEZ_Panda_II_Application1
    public class Program
        public static void Main()
         SPI.Configuration MyConfig = new SPI.Configuration((Cpu.Pin)FEZ_Pin.Digital.Di0,false,0,0,false,true,10,SPI.SPI_module.SPI1);
            SPI MySPI = new SPI(MyConfig);
            byte[] tx_data = new byte[8]; 
            byte[] rx_data = new byte[8];
            while (true) {
                MySPI.WriteRead(tx_data, rx_data);           


With frequency o 150kHz instead of the used 10kHz no expection is raised.




Please double check that you installed the latest SDK the version number should be when you look up hardware capabilities in MFDeploy.


I checked the version and it is definitely
I desintalled the GHI SDK, checked that all files are gone and installed the latest SDK again with the same results.
I checked the versions of all DLL files in the assemblies directory and all are with version except of the file “GHIElectronics.NETMF.W5100.Dhcp.dll” which has




There is a file called “release notes” right in the GHI SDK installed on your PC. Please open it and match it to this


I checked, it matches.

GHI Electronics, LLC
SDK Version 1.0.14
April 11, 2011



Please update the firmware and then recheck the firmware version number using MFDeploy. There is a video under the download page on how to do that. Firmware version number should be

[quote]SDK Version 1.0.14 April 11, 2011
• USBizi (FEZ Mini, FEZ Domino, FEZ Rhino, FEZ Panda) V


sorry it was my mistakte. :-[
After upgrading the internal firmware everything works fine down to 1kHz.
Thanks you for your great support.