Jan-Peter von Hunnius
add7ace674
- Remap opcodes 0x01-0x0F from duplicate LD to Invalid (undefined on real hardware) - Fix JCN condition bit mapping per datasheet: C1=Carry, C2=ACC zero, C3=TEST pin - Fix DAA instruction to clear carry when no 4-bit overflow occurs - Rewrite fibonacci demo program with correct opcodes (FIM, CLB, LD, ADD, WRM, XCH, ISZ) - Regenerate fibonacci.bin and fibonacci_output.bin with correct opcodes - Update all tests to match corrected JCN condition codes - Update plan document and README to reflect changes
82 lines
No EOL
3.4 KiB
Markdown
82 lines
No EOL
3.4 KiB
Markdown
# MCS-4 Programs
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This directory contains binary program files for the Intel MCS-4 emulator.
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## Available Programs
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### fibonacci.bin
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- **Size:** 17 bytes
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- **Description:** Fibonacci sequence generator (stores results in RAM)
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- **Algorithm:** Calculates first 8 Fibonacci numbers using registers R0-R3 and RAM
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- **Instructions Used:** FIM, CLB, LD, ADD, WRM, XCH, ISZ, NOP
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- **Output:** Results stored in RAM via WRM
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### fibonacci_output.bin ✨ **RECOMMENDED**
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- **Size:** 23 bytes
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- **Description:** Enhanced Fibonacci sequence generator with output port visibility
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- **Algorithm:** Calculates first 8 Fibonacci numbers and outputs them to RAM + output ports
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- **Instructions Used:** FIM, CLB, LD, ADD, WRM, WMP, XCH, SRC, ISZ, NOP
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- **Output:** Each Fibonacci number visible on output ports during execution
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- **Features:** Real-time visibility of calculation progress
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### io_demo.bin ✨ **NEW**
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- **Size:** 32 bytes (16 instructions × 2 bytes each)
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- **Description:** I/O port demonstration program for Intel 4001
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- **Algorithm:** Writes values to I/O ports 0-3 and reads them back
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- **Instructions Used:** LDM, SRC, WRM, RDM, JCN
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- **Output:** Demonstrates I/O port functionality with visible port states
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- **Features:** Shows I/O port read/write operations and latching behavior
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## Usage
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Programs are automatically loaded by the emulator. Use the `--file` option to specify a different program:
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```bash
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# Use default fibonacci program (RAM-based)
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cargo run -- --system basic
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# Use enhanced fibonacci program with output ports ✨
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cargo run -- --system basic --file programs/fibonacci_output.bin
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### io_demo.bin ✨ **NEW**
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- **Size:** Assembly source (needs compilation to binary)
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- **Description:** I/O port demonstration program for Intel 4001
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- **Algorithm:** Writes values 1-4 to I/O ports 0-3 and reads them back
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- **Instructions Used:** LDM, SRC, WRM, RDM, JCN
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- **Output:** Demonstrates I/O port functionality with visible port states
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- **Features:** Shows I/O port read/write operations and latching behavior
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# Use I/O demonstration program ✨
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cargo run -- --system mcs4_io_demo --file programs/io_demo.bin
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# Use specific program
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cargo run -- --system basic --file programs/myprogram.bin
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```
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## Adding New Programs
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1. Create your MCS-4 assembly program
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2. Assemble it into raw binary format (big-endian byte pairs)
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3. Save as `.bin` file in this directory
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4. Update this README with program details
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## Program Format
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MCS-4 programs are stored as raw binary data where each instruction is represented as 8-bit bytes. Multi-byte instructions (like addresses) use big-endian format.
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## Program Development Tips
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### Making Programs Visible
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- **Use Output Ports:** Write results to output ports via `WRR` (ROM port) or `WMP` (RAM port) for visibility
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- **SRC Instruction:** Select target chip/address with `SRC` before I/O operations
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- **Real-time Output:** Numbers appear on output ports during execution
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- **System Monitoring:** Watch RAM contents and output port states in real-time
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### Example Output Port Usage
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```asm
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FIM R0, 0x05 ; Load register pair R0/R1 with address (R0=0, R1=5)
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SRC R0 ; Send register control from R0/R1 — selects chip/port
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WRM ; Write ACC to RAM main memory at selected address
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```
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> **Note**: `SRC` takes a register *pair* number (0-7), not a direct port number. The register pair contents form the 8-bit address used for I/O and RAM operations. See the Intel 4004 datasheet for details. |