FTDI_simple_alarm/README.md

# FTDI_simple_alarm

Use a USB-Serial Converter like the FT232RL for activating a buzzer. Simple and cheap (~1,75€)

## Features:
* works on GNU/Linux only
* no drivers or other software/libs are requidered
* triggerd via bash or service daemon

## Limitations:
* works safe on system with only one `/dev/ttyUSB` device
* no other task can use the FTDI device for other things

## Handware:
1. FT232RL Breakout board ~1,5€
2. NPN Transistor like 2N2222A ~0,0€
3. Active Buzzer 5V ~0,25€

### Schematics:
![](https://git.mosad.xyz/localhorst/FTDI_simple_alarm/raw/commit/13a1200aea0d3dfb92495ae7d7f4993ddc4338f6/img/schematics.png)

### FTDI EEPROM
To invert the TXD pin on the FTDI device, programming the EEPROM is needed. With the Windoofs tool "FTDI_Prog" the Template `ft232rl_alert.xml` is uplouded. For GNU/Linux is [ftx-prog](https://github.com/richardeoin/ftx-prog) available. The only difference to default is the inverted TXD pin.

## Software:

### Commmon Distributions

Make shure the device is recocntied as ttyUSB after plug in with `dmesg`.<br/>
Edit the alarm.sh with your device name, like `/dev/ttyUSB0`. <br/>
Run `bash ./alarm.sh` for starting the alarm.<br/>

### openWrt

`opkg update`<br/>
`opkg install kmod-usb-serial`<br/>
`opkg install kmod-usb-serial-ftdi`<br/>

Make shure the device is recocntied as ttyUSB after plug in with `dmesg`.<br/>
Edit the alarm.sh with your device name, like `/dev/ttyUSB0`. <br/>
Run `bash ./alarm.sh` for starting the alarm.<br/>

### Service
todo