Summary of Bluetooth Net Monitor
This article describes a DIY Bluetooth Network Monitor designed to display real-time statistics like download/upload speeds, ping, and packet loss. The device uses an ATmega328P microcontroller, a 1.8-inch color LCD, and a Bluetooth module powered by USB. It connects to a router running a shell script that gathers data via a USB-to-serial converter. The monitor features two display modes showing rates, history graphs, and network diagnostics.
Parts used in the Bluetooth Net Monitor:
- ATmega328P @ 20MHz
- 160×128 1.8″ colour LCD
- Bluetooth module
- USB power source (5V)
- Button for brightness and mode control
- A8 paper display holder with back clippy part removed
- Rubber feet
- Shell script on Debian Linux router
- USB-to-serial converter using CP2102
Whenever I want to see why a download is going a little slow or getting lag on an online game I’d have to log in to my routers web page or SSH in to see if its someone else in the house downloading/uploading, the net connection going wonky or just the server, this was a bit annoying to do, so I made this device to constantly show network statistics.
Monitor
The monitor uses an ATmega328P @ 20MHz, 160×128 1.8″ colour LCD, a Bluetooth module, is powered by USB’s 5V, has a button for changing LCD brightness (long press) and display mode (short press) and since it’s powered by USB I added support for V-USB. The plastic part with everything screwed on to is an A8 paper display holder with the back clippy part removed and some rubber feet added.
The monitor has a few modes for displaying data:
Display mode 1
- Down sync
- Up sync
- Down rate
- Up rate
- History graph for the past 25 seconds
- Ping
- Packet loss
- WAN IP
- Time
- Email notification
Display mode 2
- Down rate
- Up rate
- Large history graph for the past 40 seconds
I’ll probably add more display modes sometime, like showing CPU usage etc. from the PC that its getting power from by making use of V-USB.
Getting the data
The router (my router is a PC running Debian Linux) runs a shell script which gets down and up speeds of the WAN interface, first hop ping, ping packet loss, WAN IP and everything else, it then sends this data to a serial port (which in this case it’s a USB-to-serial converter using a CP2102) with a serial Bluetooth module attached, data is then sent to the other Bluetooth module in the net monitor which is then displayed on the LCD.
For more detail: Bluetooth Net Monitor
- How does the monitor get network data?
The router runs a shell script that gathers data and sends it to a serial port connected to a Bluetooth module. - What microcontroller is used in the project?
The monitor uses an ATmega328P running at 20MHz. - Can the display show historical data?
Yes, Display mode 1 shows a history graph for the past 25 seconds, while Display mode 2 shows a large graph for the past 40 seconds. - How is the device powered?
The device is powered by USB's 5V and supports V-USB. - What specific network metrics can be displayed?
It displays down sync, up sync, down rate, up rate, ping, packet loss, WAN IP, time, and email notifications. - How do you change the display settings?
A short press changes the display mode and a long press changes the LCD brightness. - What hardware converts the serial data for transmission?
A USB-to-serial converter using a CP2102 chip is used to send data to the Bluetooth module. - What operating system runs the router script?
The example router runs Debian Linux.
