White Rose Engineering

Just another HackHut site
Admin: lackawanna

Training your PID

Training your PID

Control theory must be on the short list for the most important subject that no one talks about. Break open a hobbyist robotics book and you are lucky if control systems are even mentioned. Control systems run our cars, fire our multi-million dollar missiles, and keep our buildings at the right temperature. The phase locked loops …..

Read the Rest

Share

DTR-less Reset Circuitry for the AVR

DTR-less Reset Circuitry for the AVR

The USART-based bootloader is probably the most popular way of burning code to the AVR. The Arduino, for one, uses this method.

For example say you were using a FTDI cable to talk to your Arduino. First the USB connector end of the cable would go into your host computer. The other end of the …..

Read the Rest

Share

Easy I2C: Pull-ups optional

Easy I2C: Pull-ups optional

The I2C interface is relatively uncomplicated to write for on the AVR, not withstanding all the details of the protocol and all the messages generated by the AVR hardware. The more advanced AVR microcontrollers, support the I2C two wire interface – three wires if counting ground. It is not called I2C in the Atmel documentation however. …..

Read the Rest

Share

Using V-USB and the HID Class (Part III of III)

Using V-USB and the HID Class (Part III of III)

Example Three

Create a new example directory and set it up as before in example one. Next edit usbconfig.h and change the values to the following.

Set USB_CFG_HAVE_INTRIN_ENDPOINT to 1,
set USB_CFG_DEVICE_CLASS to 0,
set USB_CFG_INTERFACE_CLASS to 3,
set USB_CFG_HID_REPORT_DESCRIPTOR_LENGTH to 34, and
set USB_CFG_IMPLEMENT_FN_WRITE to 1.

The source code for example three is given in the download.

The report descriptor now …..

Read the Rest

Share

Using V-USB and the HID Class (Part II of III)

Using V-USB and the HID Class (Part II of III)

The HID Interface

All HID interfaces are required to have one IN endpoint, besides the control endpoint zero. If there is no IN endpoint, a HID device will not be created on the host. This is so even if the HID interface does not send any input reports. At least this is how the Linux kernel behaves.

In …..

Read the Rest

Share

Using V-USB and the HID Class (Part I of III)

Using V-USB and the HID Class (Part I of III)

USB can be quite a complex interface to learn. It is definitely not as easy to explain or as intuitive as the well known serial port. The specification for USB is hundreds of pages long. Books such as USB Complete by Jan Axelson and USB Design by Example by John Hyde are just as big. …..

Read the Rest

Share

A Logic Analyzer using Audacity

A Logic Analyzer using Audacity

If you are interested in observing digital data lines, such as the I2C bus, but do not have a logic analyzer — yet are lucky enough to still have a parallel port on your computer, this hack (I won’t say program) hopefully will help.  It captures the logic levels present at the input of the two data pins, D0 …..

Read the Rest

Share

Be self-reliant, compost

Be self-reliant, compost

Composting might not be the geekiest thing at the moment – no iPhone apps currently exist for it from what I can determine.  Nevertheless it has been happening on this planet since organisms started living here and it is still very important.  30% of our waste is organic material which could be composted but unfortunately isn’t.

There are two processes …..

Read the Rest

Share

Hell-writing using a AVR keyer

Image of Feld Hell decoding output

There is no school like the old school and this fax technology from the 20′s using psycho-visual perception for image synchronization is just that.   A fax mark is represented by a carrier; and if there is no carrier there is no mark.  After a period of time, 7/122.5 seconds for the Feld-Hell standard, the tape is advanced and …..

Read the Rest

Share
Return top

Welcome to HackHut