# `otopcua-s7-cli` — Siemens S7 test client

Ad-hoc probe / read / write / subscribe tool for Siemens S7-300 / S7-400 /
S7-1200 / S7-1500 (and compatible soft-PLCs) over S7comm / ISO-on-TCP port 102.
Uses the **same** `S7Driver` the OtOpcUa server does (S7.Net under the hood).

Fourth of four driver test-client CLIs.

## Build + run

```powershell
dotnet run --project src/ZB.MOM.WW.OtOpcUa.Driver.S7.Cli -- --help
```

## Common flags

| Flag | Default | Purpose |
|---|---|---|
| `-h` / `--host` | **required** | PLC IP or hostname |
| `-p` / `--port` | `102` | ISO-on-TCP port (rarely changes) |
| `-c` / `--cpu` | `S71500` | S7200 / S7200Smart / S7300 / S7400 / S71200 / S71500 |
| `--rack` | `0` | Hardware rack (S7-400 distributed setups only) |
| `--slot` | `0` | CPU slot (S7-300 = 2, S7-400 = 2 or 3, S7-1200/1500 = 0) |
| `--timeout-ms` | `5000` | Per-operation timeout |
| `--verbose` | off | Serilog debug output |

## PUT/GET must be enabled

S7-1200 / S7-1500 ship with PUT/GET communication **disabled** by default.
Enable it in TIA Portal: *Device config → Protection & Security → Connection
mechanisms → "Permit access with PUT/GET communication from remote partner"*.
Without it the CLI's first read will surface `BadNotSupported`.

## S7 address grammar cheat sheet

| Form | Meaning |
|---|---|
| `DB1.DBW0` | DB number 1, word offset 0 |
| `DB1.DBD4` | DB number 1, dword offset 4 |
| `DB1.DBX2.3` | DB number 1, byte 2, bit 3 |
| `DB10.STRING[0]` | DB 10 string starting at offset 0 |
| `M0.0` | Merker bit 0.0 |
| `MW0` / `MD4` | Merker word / dword |
| `IW4` | Input word 4 |
| `QD8` | Output dword 8 |

## Commands

### `probe`

```powershell
# S7-1500 — default probe MW0
otopcua-s7-cli probe -h 192.168.1.30

# S7-300 (slot 2)
otopcua-s7-cli probe -h 192.168.1.31 -c S7300 --slot 2 -a DB1.DBW0
```

### `read`

```powershell
# DB word
otopcua-s7-cli read -h 192.168.1.30 -a DB1.DBW0 -t Int16

# Float32 from DB dword
otopcua-s7-cli read -h 192.168.1.30 -a DB1.DBD4 -t Float32

# Merker bit
otopcua-s7-cli read -h 192.168.1.30 -a M0.0 -t Bool

# 80-char S7 string
otopcua-s7-cli read -h 192.168.1.30 -a DB10.STRING[0] -t String --string-length 80
```

### `write`

```powershell
otopcua-s7-cli write -h 192.168.1.30 -a DB1.DBW0 -t Int16 -v 42
otopcua-s7-cli write -h 192.168.1.30 -a DB1.DBD4 -t Float32 -v 3.14
otopcua-s7-cli write -h 192.168.1.30 -a M0.0 -t Bool -v true
```

**Writes to M / Q are real** — they drive the PLC program. Be careful what you
flip on a running machine.

### `subscribe`

```powershell
otopcua-s7-cli subscribe -h 192.168.1.30 -a DB1.DBW0 -t Int16 -i 500
```

S7comm has no native push — the CLI polls through `PollGroupEngine` just like
Modbus / AB.