FEZ Spider on TinyCLR OS

I want to use FEZ Spider on Visual Studio 2017, so I installed EMX bootloader, EMX firmware in FEZ Spider, and TinyCLR OS in VS2017.

But when I tried to run basic LED program, debugger returned this error.

Found debugger!

Create TS.

Loading Deployment Assemblies.

Attaching deployed file.

Assembly: mscorlib (

Error: the reference mscorlib cannot be used with this version of the firmware.

Firmware checksum 0x47604AAF does not match the assembly checksum 0xB8544950.


The debugging target runtime is loading the application assemblies and starting execution.

Cannot find any entrypoint!


Waiting for debug commands…

How do I do to run program?

From where have you get firmware ? Which version of TinyClr OS do you use ?

I got firmware from official document page :

TinyClr OS version is 1.0.101.

EMX firmware version is 0.12 so you have to use TinyCLR and nuget packages 0.12, not the latest. The is very important especially with all pre production releases

If you need the latest then you can use the sources to build it.

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That’s what I have guessed: Firmware version must match TinyClr OS version.
Firmware for legacy boards (Spider is one of them) are not more build and downloadable on GHI website. But you can build yourself as @Gus_Issa said.

If you are not ready to build yourself. Use vsix 0.12 version, Library 0.12 version and so you can use Firmware 0.12.

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Thank you for your answer.
I installed TinyCLR OS and nuget 0.12 from https://docs.ghielectronics.com/software/tinyclr/downloads.html,
it seems to connect VS and Spider.

But I received this message from debugger now.

Found debugger!

Create TS.

Loading Deployment Assemblies.

Attaching deployed file.

Assembly: mscorlib ( Attaching deployed file.

Assembly: GHIElectronics.TinyCLR.Devices ( Attaching deployed file.

Assembly: TinyCLRApplication2 ( Attaching deployed file.

Assembly: TinyCLRApplication2 ( Resolving.

Link failure: some assembly references cannot be resolved!!

Assembly: TinyCLRApplication2 ( needs assembly ‘mscorlib’ (

Assembly: TinyCLRApplication2 ( needs assembly ‘GHIElectronics.TinyCLR.Devices.Gpio’ (

Error: a3000000

Waiting for debug commands…

Do I need another package?

Uninstall the TinyCLR project system and install version 0.12

When I delete old program in Spider, debugger not returned error.
I don’t know how to use TinyCLR OS, so I will ask other thread.

Thank you very much!