diff --git a/CMakeLists.txt b/CMakeLists.txt
index 3a4f176..ef8f497 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -63,6 +63,18 @@ add_custom_command(
           "${CMAKE_CURRENT_SOURCE_DIR}/lib/syscalls_cg.def" >
           "${CMAKE_CURRENT_BINARY_DIR}/FxOS_SyscallDefs_CG.c"
   DEPENDS lib/syscalls_cg.def)
+add_custom_command(
+  OUTPUT "${CMAKE_CURRENT_BINARY_DIR}/FxOS_AsmDefs_SH3.c"
+  COMMAND xxd -i -n FxOS_AsmDefs_SH3
+          "${CMAKE_CURRENT_SOURCE_DIR}/lib/sh3.def" >
+          "${CMAKE_CURRENT_BINARY_DIR}/FxOS_AsmDefs_SH3.c"
+  DEPENDS lib/sh3.def)
+add_custom_command(
+  OUTPUT "${CMAKE_CURRENT_BINARY_DIR}/FxOS_AsmDefs_SH4.c"
+  COMMAND xxd -i -n FxOS_AsmDefs_SH4
+          "${CMAKE_CURRENT_SOURCE_DIR}/lib/sh4.def" >
+          "${CMAKE_CURRENT_BINARY_DIR}/FxOS_AsmDefs_SH4.c"
+  DEPENDS lib/sh4.def)
 
 set(fxos_core_SOURCES
   lib/analysis.cpp
@@ -80,6 +92,8 @@ set(fxos_core_SOURCES
   lib/vspace.cpp
   "${CMAKE_CURRENT_BINARY_DIR}/FxOS_SyscallDefs_FX.c"
   "${CMAKE_CURRENT_BINARY_DIR}/FxOS_SyscallDefs_CG.c"
+  "${CMAKE_CURRENT_BINARY_DIR}/FxOS_AsmDefs_SH3.c"
+  "${CMAKE_CURRENT_BINARY_DIR}/FxOS_AsmDefs_SH4.c"
 
   lib/ai/RelConst.cpp
   lib/util/bson.cpp
diff --git a/include/fxos/util/Buffer.h b/include/fxos/util/Buffer.h
index 08ce09f..2aabfab 100644
--- a/include/fxos/util/Buffer.h
+++ b/include/fxos/util/Buffer.h
@@ -46,6 +46,9 @@ struct Buffer
     /* Create a buffer by copying and resizing another buffer */
     Buffer(Buffer const &other, size_t new_size, int fill = 0x00);
 
+    /* Buffer initialized from pure data. */
+    Buffer(void const *ptr, size_t size, std::string const &path = "(inline)");
+
     /* Buffer size */
     size_t size;
     /* Data */
diff --git a/lib/util/Buffer.cpp b/lib/util/Buffer.cpp
index 5d856d1..9bd6b79 100644
--- a/lib/util/Buffer.cpp
+++ b/lib/util/Buffer.cpp
@@ -123,3 +123,11 @@ Buffer::Buffer(Buffer const &other, size_t new_size, int fill):
     memcpy(this->data.get(), other.data.get(), std::min(new_size, other.size));
     this->path = other.path;
 }
+
+Buffer::Buffer(void const *ptr, size_t ptrsize, std::string const &path)
+{
+    this->data = std::make_unique<char[]>(ptrsize);
+    memcpy(this->data.get(), ptr, ptrsize);
+    this->size = ptrsize;
+    this->path = path;
+}
diff --git a/shell/dot.cpp b/shell/dot.cpp
index cae70e4..cf7eb1c 100644
--- a/shell/dot.cpp
+++ b/shell/dot.cpp
@@ -24,23 +24,6 @@ void _dot(Session &s, std::vector<std::string> const &files, bool absolute)
     lex_include(paths);
 }
 
-//---
-// .dt
-//---
-
-static std::string parse_dot_dt(Session &session, Parser &parser)
-{
-    std::string filename = parser.str();
-    parser.end();
-    return session.file(filename);
-}
-
-void _dot_dt(Session &, std::string filename)
-{
-    Buffer buf(filename);
-    FxOS::load_instructions(buf);
-}
-
 //---
 // Command registration
 //---
@@ -53,14 +36,3 @@ static ShellCommand _dot_cmd(
 Reads file paths from its string arguments, and executes each of them as a
 sequence of commands in the order of the command line.
 )");
-
-static ShellCommand _dot_dt_cmd(
-    ".dt", [](Session &s, Parser &p) { _dot_dt(s, parse_dot_dt(s, p)); },
-    [](Session &s, Parser &p) { parse_dot_dt(s, p); },
-    "Include Disassembly Table",
-    R"(
-.dt "<file>"
-
-Loads a disassembly table from the specified file. This command is mostly
-designed to be used in startup scripts.
-)");
diff --git a/shell/main.cpp b/shell/main.cpp
index d88e41b..3f13c90 100644
--- a/shell/main.cpp
+++ b/shell/main.cpp
@@ -413,6 +413,18 @@ int main(int argc, char **argv)
     if(histfile[0])
         read_history(histfile);
 
+    /* Load embedded instruction tables */
+
+    extern char const FxOS_AsmDefs_SH3[];
+    extern int FxOS_AsmDefs_SH3_len;
+    Buffer defSH3(FxOS_AsmDefs_SH3, FxOS_AsmDefs_SH3_len, "lib/sh3.def");
+    FxOS::load_instructions(defSH3);
+
+    extern char const FxOS_AsmDefs_SH4[];
+    extern int FxOS_AsmDefs_SH4_len;
+    Buffer defSH4(FxOS_AsmDefs_SH4, FxOS_AsmDefs_SH4_len, "lib/sh4.def");
+    FxOS::load_instructions(defSH4);
+
     /* Load a project as specified by command-line arguments */
     load_initial_project(s, opts.load, opts.load_is_by_name);
     /* If none was given or it failed, load the most recent project */