added M records

simulator_SIC_XE/README.md

@@ -1,30 +1,65 @@
 # SIC/XE Simulator
 
-A complete SIC/XE architecture simulator with instruction execution, device I/O, and memory management.
+A complete SIC/XE architecture simulator with instruction execution, device I/O, memory management, and assembler.
 
 ## Quick Start
 
-The easiest way to build and run the simulator:
+### Building the Project
+
+```bash
+make
+```
+
+This will build:
+- `target/bin/simulator_exec` - The main simulator
+- `target/bin/assembler` - The SIC/XE assembler
+- `target/bin/simulator_qt` - Qt GUI version (if Qt is available)
+
+### Using the Assembler
+
+Assemble a SIC/XE assembly file to object code:
+
+```bash
+./target/bin/assembler <file.asm>
+```
+
+**Example:**
+```bash
+./target/bin/assembler res/test_format4.asm
+```
+
+This will:
+- Parse and assemble the input file
+- Generate modification records (M records) for format 4 instructions
+- Create `<file>.obj` with the object code
+- Display the object code and symbol table
+
+**Sample Output:**
+```
+H TESTF4 0003E8 00001B
+T 0003E8 1B 031003F70F1003FA4B1003FD4F2C090000000000000100004F2BFD
+M 0003E9 05
+M 0003ED 05
+M 0003F1 05
+E 0003E8
+```
+
+### Running the Simulator
 
 ```bash
 make run
 ```
 
-This single command will:
-- Configure the build system (if needed)
-- Compile all source files
-- Link the executable 
-- Run the simulator
+This will build and run the simulator with the default program.
 
 ## Build Commands
 
 |    Command   |                   Description                      |
 |--------------|----------------------------------------------------|
-| `make`       | Build the project                                  |
+| `make`       | Build all executables                              |
 | `make build` | Build the project                                  |
-| `make run`   | Build run the simulator                            |
+| `make run`   | Build and run the simulator                        |
 | `make clean` | Clean build artifacts                              |
-| `make run`   | Clean build artifacts, build and run the simulator |
 
 
 ## Project Structure