diff --git a/test/mains/README.md b/test/mains/README.md
index 9ef9666d..e46d3433 100644
--- a/test/mains/README.md
+++ b/test/mains/README.md
@@ -1,5 +1,18 @@
-# Method testing
+# Mains testing
 
-Test Whole methods by their output. Using the main method (implicitly)
+Test methods by their output and exit codes (return, since it is the main). 
 
-Through Interpreter
+There are only two tests here, one for interpreter, one for arm.
+Both run the same tests. The actual ruby code that is run is in the source dir.
+Test methods are generated, one for each source file.
+
+File names follow [name,stdout,exitcode] joined by _ pattern. Stdout may be left blank,
+but exit code must be supplied.
+
+Obviously the arm tests need an arm platform. This may be defined by ARM_HOST,
+eg for simulated ARM_HOST=localhost
+
+Also port and user may be specified with ARM_PORT and ARM_USER , they default to
+2222 and pi if left blank.
+SSH keys must be set up so no passwords are required (and the users private key may
+  not be password protected)
diff --git a/test/mains/helper.rb b/test/mains/helper.rb
index 78073e8d..bb161258 100644
--- a/test/mains/helper.rb
+++ b/test/mains/helper.rb
@@ -1,14 +1,4 @@
 require_relative '../helper'
 
 module Mains
-  class MainsTest < MiniTest::Test
-    include Risc::Ticker
-    def setup;end
-
-    def run_main_check(input , stdout , exit_code)
-      run_main(input)
-      assert_equal stdout , @interpreter.stdout , "Wrong stdout"
-      assert_equal exit_code , get_return.to_s , "Wrong exit code"
-    end
-  end
 end
diff --git a/test/mains/source/add__4.rb b/test/mains/source/add__4.rb
new file mode 100644
index 00000000..7758ea60
--- /dev/null
+++ b/test/mains/source/add__4.rb
@@ -0,0 +1 @@
+return 2 +2
diff --git a/test/mains/test_arm.rb b/test/mains/test_arm.rb
new file mode 100644
index 00000000..783d0c57
--- /dev/null
+++ b/test/mains/test_arm.rb
@@ -0,0 +1,88 @@
+require_relative 'helper'
+require 'net/ssh'
+require 'net/scp'
+
+module Mains
+  class TestArm < MiniTest::Test
+
+    # runnable_methods is called by minitest to determine which tests to run
+    def self.runnable_methods
+      all = Dir["test/mains/source/*.rb"]
+      tests =[]
+      all.each do |file_name|
+        fullname = file_name.split("/").last.split(".").first
+        name , stdout , exit_code = fullname.split("_")
+        method_name = "test_#{name}"
+        tests << method_name
+        input = File.read(file_name)
+        self.send(:define_method, method_name ) do
+          out , code = run_main(input , name)
+          assert_equal stdout , out , "Wrong stdout #{name}"
+          assert_equal exit_code , code.to_s , "Wrong exit code #{name}"
+        end
+      end
+      tests
+    end
+
+    DEBUG = true
+
+    def setup
+      Risc.machine.boot
+    end
+
+    def run_main(input , file)
+      Vool::VoolCompiler.ruby_to_binary( "class Space;def main(arg);#{input};end;end" )
+      writer = Elf::ObjectWriter.new(Risc.machine)
+      writer.save "test/#{file}.o"
+      run_ssh(file)
+    end
+
+    def run_ssh( file )
+      host = ENV["ARM_HOST"]
+      return unless host
+      port = (ENV["ARM_PORT"] || 2222)
+      user = (ENV["ARM_USER"] || "pi")
+      binary_file = "/tmp/#{file}"
+      object_file = binary_file + ".o"
+      Net::SCP.start(host, user , port: port ) do |scp|
+        puts "Copying test/#{file}.o to #{object_file}" if DEBUG
+        scp.upload! "test/#{file}.o",  object_file
+      end
+      Net::SSH.start(host, user , port: port ) do |ssh|
+        puts "Linking #{object_file}" if DEBUG
+        stdout , exit_code = ssh_exec!(ssh , "ld -N -o #{binary_file} #{object_file}")
+        assert_equal 0 , exit_code , "Linking #{binary_file} failed"
+        puts "Running #{binary_file}" if DEBUG
+        stdout , exit_code = ssh_exec!(ssh , binary_file)
+        puts "Result #{stdout} #{exit_code}" if DEBUG
+        return stdout , exit_code
+      end
+    end
+
+    def ssh_exec!(ssh, command)
+      stdout_data = ""
+      exit_code = nil
+      ssh.open_channel do |channel|
+        channel.exec(command) do |ch, success|
+          unless success
+            raise "FAILED: couldn't execute command (ssh.channel.exec)"
+          end
+          channel.on_data do |c,data|
+            stdout_data+=data
+          end
+          channel.on_extended_data do |c,type,data|
+            raise "#{ssh} received stderr #{data}"
+          end
+          channel.on_request("exit-status") do |c,data|
+            exit_code = data.read_long
+          end
+          channel.on_request("exit-signal") do |c, data|
+            raise "#{ssh} received signal #{data.read_long}"
+          end
+        end
+      end
+      ssh.loop
+      [stdout_data, exit_code]
+    end
+  end
+end
diff --git a/test/mains/test_puts.rb b/test/mains/test_puts.rb
deleted file mode 100644
index eb520de4..00000000
--- a/test/mains/test_puts.rb
+++ /dev/null
@@ -1,11 +0,0 @@
-require_relative 'helper'
-
-module Mains
-  class TestPuts < MainsTest
-
-    def test_ruby_puts
-      run_main_file "puts"
-    end
-
-  end
-end