Demo mode¶

The demo device is a simulated serial device for exploring termapy without hardware. See Installation for how to start it.

Entering demo mode¶

termapy --demo                   # from the command line

Or from within termapy:

/demo: switch to the demo config (creates it if needed)
/demo.force: reset demo to defaults and switch to it

What you get¶

The demo creates a complete project at termapy_cfg/demo/ with:

A simulated device called BASSOMATIC-77 (the natural successor to Dan Aykroyd's '76) that responds to AT commands, GPS/NMEA queries, and binary Modbus RTU frames
5 toolbar buttons: Demo Help, AT Demo, Info, Probe, TempPlot
6 scripts: welcome, at_demo, gps_demo, smoke_test, status_check, var_demo
3 protocol test files: at_test, bitfield_inline, modbus_inline
4 plugins: cmd (custom shortcut), probe (device query), temp_plot (sparkline), traffic (RX/TX byte tap)

Device commands¶

The simulated device supports three protocols:

AT commands (text)¶

Command	Response
`AT`	`OK` (connection test)
`AT+INFO`	Device info, uptime, free memory
`AT+TEMP`	Simulated temperature reading (22-25C)
`AT+LED on\\|off`	Toggle LED state
`AT+STATUS`	LED state, uptime, connections
`AT+NAME?` / `AT+NAME=val`	Query or set device name
`AT+BAUD?` / `AT+BAUD=val`	Query or set baud rate
`AT+PROD-ID`	Product ID (`BASSOMATIC-77`)
`AT+RESET`	Simulated reboot sequence
`AT+HELP.JSON`	Device command help (JSON)
`AT+TEXTDUMP <n>`	Emit text readings
`AT+BINDUMP <n>`	Emit binary records
`mem <addr> [len]`	Hex memory dump

GPS / NMEA¶

Command	Response
`$GPGGA`	Position fix (lat, lon, altitude, satellites)
`$GPRMC`	Recommended minimum nav (pos, speed, date)
`$GPGSA`	DOP and active satellites
`$GPGSV`	Satellites in view

Modbus RTU (binary)¶

Use /proto.send with hex bytes (CRC included):

/proto.send 01 03 00 00 00 01 84 0A       # read 1 register
/proto.send 01 06 00 05 04 D2 1B 56       # write register 5 = 1234
/proto.send 01 03 00 05 00 01 94 0B       # read back register 5

Supports function codes 0x03 (read holding registers) and 0x06 (write single register) with CRC16 enforced.

Data capture commands¶

Text capture¶

/cap.text readings.txt timeout=3s cmd=AT+TEXTDUMP 50

Binary capture: mixed record to CSV¶

/cap.struct mixed.csv fmt=Label:S1-10 Counter:U11 Val16:U13-12 Val32:U17-14 Temp:F21-18 records=20 cmd=AT+BINDUMP 20

Binary capture: single type¶

/cap.struct u16_data.csv fmt=Value:U2-1 records=50 cmd=AT+BINDUMP u16 50

Demo plugins¶

Plugin	Command	What it does
cmd.py	`/cmd`	Custom shortcut, wraps a device command
probe.py	`/probe`	Device survey, send/receive cycle with output
temp_plot.py	`/temp_plot`	Sample temperature N times, draw ASCII sparkline
traffic.py	`/traffic.*`	RX/TX byte tap: count, hex-dump, rate, snoop (passive observer pattern)

probe.py is the best starting template for plugins that send and parse a single device response. traffic.py is the template for plugins that need to watch the byte stream without disrupting normal operation -- it demonstrates the ctx.serial.rx_observer() / ctx.serial.tx_observer() context managers (see Writing Plugins for the full pattern).

`/traffic.*` subcommands¶

Subcommand	Args	What it does
`/traffic.count`	`<cmd>`	Run a command and report TX/RX bytes during it
`/traffic.hexdump`	`<file> [duration]`	Tee timestamped hex of all I/O to a file (default 5s)
`/traffic.rate`	`[duration]`	Bytes/sec rate over a window (default 5s)
`/traffic.snoop`	`<hex> [timeout=<dur>]`	Block until a hex byte pattern appears in RX

Examples against the demo:

demo> /traffic.count AT+VER
  TX: 7  RX: 12  bytes

demo> /traffic.rate 3s
  Sampling for 3.0s...
  TX: 0 bytes (0.0 B/s)
  RX: 28 bytes (9.3 B/s)

demo> /traffic.hexdump capture.log 10s

demo> /traffic.snoop 56 45 52 timeout=2s    # wait for "VER" in RX
  Matched 565452 at offset 14