examples Package¶

`examples` Package¶

pylibftdi examples

`bit_server` Module¶

bit_server.py - remote HTTP interface to bit-bangged FTDI port This runs as a web server, connect to port 8008

Change HTTP_PORT for different port number or supply alternate as args[1]

Requires:

pylibftdi

class pylibftdi.examples.bit_server.ReqHandler(request, client_address, server)[source]¶

Bases: BaseHTTPRequestHandler

do_GET()[source]¶

do_POST()[source]¶

send_head()[source]¶

class pylibftdi.examples.bit_server.ThreadingServer(server_address, RequestHandlerClass, bind_and_activate=True)[source]¶: Bases: ThreadingMixIn, HTTPServer

pylibftdi.examples.bit_server.get_page()[source]¶

pylibftdi.examples.bit_server.runserver(port=8008)[source]¶

`lcd` Module¶

Write a string (argv[1] if run from command line) to a HD44780 LCD module connected via a FTDI UM232R/245R module using pylibftdi

example usage:

# while true; > do python lcd.py $( awk ‘{print $1}’ /proc/loadavg); > sleep 5; > done

class pylibftdi.examples.lcd.LCD(device)[source]¶

Bases: object

The UM232R/245R is wired to the LCD as follows:: DB0..3 to LCD D4..D7 (pin 11..pin 14) DB6 to LCD ‘RS’ (pin 4) DB7 to LCD ‘E’ (pin 6)

__init__(device)[source]¶

init_four_bit()[source]¶: set the LCD’s 4 bit mode, since we only have 8 data lines and need at least 2 to strobe data into the module and select between data and commands.

write_cmd(x)[source]¶

write_data(x)[source]¶

data¶: This class is a descriptor for a bus of a given width starting at a given offset (0 = LSB). The device which does the actual reading and writing is assumed to be a BitBangDevice instance in the ‘device’ attribute of the object to which this is attached.

e¶: This class is a descriptor for a bus of a given width starting at a given offset (0 = LSB). The device which does the actual reading and writing is assumed to be a BitBangDevice instance in the ‘device’ attribute of the object to which this is attached.

rs¶: This class is a descriptor for a bus of a given width starting at a given offset (0 = LSB). The device which does the actual reading and writing is assumed to be a BitBangDevice instance in the ‘device’ attribute of the object to which this is attached.

pylibftdi.examples.lcd.display(string, device_id=None)[source]¶: Display the given string on an attached LCD an optional device_id can be given.

`led_flash` Module¶

Flash an LED connected via a FTDI UM232R/245R module using pylibftdi

Optionally supply a flash rate (in Hz, default 1) as an argument

pylibftdi.examples.led_flash.flash_forever(rate)[source]¶: toggle bit zero at rate Hz

pylibftdi.examples.led_flash.main()[source]¶

`list_devices` Module¶

Report connected FTDI devices. This may be useful in obtaining serial numbers to use as the device_id parameter of the Device() constructor to communicate with a specific device when more than one is present.

example usage:

$ python pylibftdi/examples/list_devices.py FTDI:UB232R:FTAS1UN5 FTDI:UM232R USB <-> Serial:FTE4FFVQ

To open a device specifically to communicate with the second of these devices, the following would be used:

>>> from pylibftdi import Device
>>> dev = Device(device_id="FTE4FFVQ")
>>>

pylibftdi.examples.list_devices.get_ftdi_device_list()[source]¶: return a list of lines, each a colon-separated vendor:product:serial summary of detected devices

pylibftdi.examples.list_devices.main()[source]¶

`magic_candle` Module¶

Magic Candle - light falling on the LDR turns on the LED, which due: to arrangement keeps the LED on until LDR/LED path is blocked

LDR (via a transistor switch - dark = ‘1’) - D0 LED (via series resistor) - D1

pylibftdi - codedstructure 2013-2014

class pylibftdi.examples.magic_candle.Candle[source]¶

Bases: object

__init__()[source]¶

run()[source]¶

be_light¶: This class is a descriptor for a bus of a given width starting at a given offset (0 = LSB). The device which does the actual reading and writing is assumed to be a BitBangDevice instance in the ‘device’ attribute of the object to which this is attached.

is_dark¶: This class is a descriptor for a bus of a given width starting at a given offset (0 = LSB). The device which does the actual reading and writing is assumed to be a BitBangDevice instance in the ‘device’ attribute of the object to which this is attached.

`midi_output` Module¶

class pylibftdi.examples.midi_output.MidiDevice(*o, **k)[source]¶

Bases: Device

__init__(*o, **k)[source]¶

Device([device_id[, mode, [OPTIONS …]]) -> Device instance

represents a single FTDI device accessible via the libftdi driver. Supports a basic file-like interface (open/close/read/write, context manager support).

Parameters:

device_id – an optional serial number of the device to open. if omitted, this refers to the first device found, which is convenient if only one device is attached, but otherwise fairly useless.
mode – either ‘b’ (binary) or ‘t’ (text). This primarily affects Python 3 calls to read() and write(), which will accept/return unicode strings which will be encoded/decoded according to the given…
encoding – the codec name to be used for text operations.
interface_select – select interface to use on multi-interface devices
device_index – optional index of the device to open, in the event of multiple matches for other parameters (PID, VID, device_id). Defaults to zero (the first device found).

The following parameters are only available as keyword parameters and override class attributes, so may be specified in subclasses.

Parameters:

lazy_open – if True, then the device will not be opened immediately - the user must perform an explicit open() call prior to other operations.
chunk_size – if non-zero, split read and write operations into chunks of this size. With large or slow accesses, interruptions (i.e. KeyboardInterrupt) may not happen in a timely fashion.
auto_detach – default True, whether to automatically re-attach the kernel driver on device close.
index – optional index into list_devices() to open. Useful in the event that multiple devices of differing VID/PID are attached, where device_index is insufficient to select as device indexing restarts at 0 for each VID/PID combination.
vid – optional vendor ID to open. If omitted, the default USB_VID_LIST is used to search for devices.
pid – optional product ID to open. If omitted, the default USB_PID_LIST is used to search for devices.

pylibftdi.examples.midi_output.scale()[source]¶

pylibftdi.examples.midi_output.volume(beat)[source]¶

`pin_read` Module¶

Display values on input pins of a BitBangDevice.

TODO:

ANSI colours / display differences in bold

example - beep on pin 1 going high:

$ pylibftdi/examples/pin_read.py -n 0.01 -m 1 -k 1 && beep

pylibftdi.examples.pin_read.display_loop(interval=1, count=0, match=None, mask=255)[source]¶

display and compare the value

Parameters:

interval – polling interval in seconds
count – number of polls to do, or infinite if 0
match – value to look for to exit early
mask – mask of read value before comparing to match

Returns:

‘ok’. either a match was made or none was requested

Return type:

bool

pylibftdi.examples.pin_read.display_value(value)[source]¶: display the given value

pylibftdi.examples.pin_read.get_value()[source]¶: get the value of the pins

pylibftdi.examples.pin_read.main(args=None)[source]¶

`serial_loopback` Module¶

test serial loopback; assumes Rx and Tx are connected

class pylibftdi.examples.serial_loopback.LoopbackTester[source]¶

Bases: object

__init__()[source]¶

bisect()[source]¶

main()[source]¶

test_iter(lengths)[source]¶

test_loopback(length)[source]¶

pylibftdi.examples.serial_loopback.test_string(length)[source]¶

`info` Module¶

Report environment info relevant to pylibftdi

example usage:

$ python3 -m pylibftdi.examples.info
pylibftdi version     : 0.15.0
libftdi version       : libftdi_version(major=1, minor=1, micro=0, version_str='1.1', snapshot_str='unknown')
libftdi library path  : /usr/local/lib/libftdi1.dylib
libusb version        : libusb_version(major=1, minor=0, micro=19, nano=10903, rc='', describe='http://libusb.info')
libusb library path   : /usr/local/lib/libusb-1.0.dylib
Python version        : 3.4.0
OS platform           : Darwin-14.1.0-x86_64-i386-64bit

pylibftdi.examples.info.ftdi_info()[source]¶

Return (ordered) dictionary contianing pylibftdi environment info

Designed for display purposes only; keys and value types may vary.

examples Package¶