`percival.carrier` package¶

`percival.carrier.devices` module¶

Created on 8 May 2015

@author: Ulrik Pedersen

class percival.carrier.devices.Command[source]¶

Represent the Command register bank:

Word 0: Device command interface word
Word 1: Sensor command interface word
Word 2: System command interface word

class percival.carrier.devices.ControlChannel[source]¶: Represent the map of Control Channels register bank

class percival.carrier.devices.DeviceSettings[source]¶: Mixin to be used by classes that implement the IDeviceSettings interface

class percival.carrier.devices.HeaderInfo[source]¶: Represent the Header Info register bank

class percival.carrier.devices.IDeviceSettings[source]¶

Interface to a Device Setting bitmap.

generate_map()[source]¶

Generate a bitmap from the device MapFields.

Returns:	a list of 32bit words

num_words¶: Number of 32bit words in the bitmap

parse_map(words)[source]¶

Parse a list of words as a bitmap and write to the relevant internal MapFields

Parameters:	words (list) – 32 bit integer words

class percival.carrier.devices.MonitoringChannel[source]¶: Represent the map of Monitoring Channel register bank

`percival.carrier.registers` module¶

Created on 5 Dec 2014

@author: Ulrik Pedersen

percival.carrier.registers.CarrierUARTRegisters = {0: (u'Header settings left', 302, 1, 1, <class 'percival.carrier.devices.HeaderInfo'>), 1: (u'Control settings left', 303, 1, 1, <class 'percival.carrier.devices.ControlChannel'>), 130: (u'Control settings bottom', 306, 1, 1, <class 'percival.carrier.devices.ControlChannel'>), 65: (u'Monitoring settings left', 304, 1, 1, <class 'percival.carrier.devices.MonitoringChannel'>), 236: (u'Command', 324, 1, 1, <class 'percival.carrier.devices.Command'>), 138: (u'Monitoring settings bottom', 307, 1, 1, <class 'percival.carrier.devices.MonitoringChannel'>), 146: (u'Header settings carrier', 308, 1, 1, <class 'percival.carrier.devices.HeaderInfo'>), 147: (u'Control settings carrier', 309, 1, 1, <class 'percival.carrier.devices.ControlChannel'>), 155: (u'Monitoring settings carrier', 310, 1, 1, <class 'percival.carrier.devices.MonitoringChannel'>), 163: (u'Header settings plugin', 311, 1, 1, <class 'percival.carrier.devices.HeaderInfo'>), 164: (u'Control settings plugin', 312, 1, 1, <class 'percival.carrier.devices.ControlChannel'>), 129: (u'Header settings bottom', 305, 1, 1, <class 'percival.carrier.devices.HeaderInfo'>), 172: (u'Monitoring settings plugin', 313, 1, 1, <class 'percival.carrier.devices.MonitoringChannel'>)}¶

Look-up table of UART addresses and the corresponding details

The key is the UART write address and each item is a tuple of:

description
UART read_addr
Number of entries
Words per entry
Corresponding implementation of the percival.carrier.devices.IDeviceSettings interface

class percival.carrier.registers.UARTRegister(start_addr)[source]¶

Represent a specific UART register on the Percival Carrier Board

__init__(start_addr)[source]¶

Constructor

Parameters:	start_addr (int) – UART start address which also functions as a look-up key to the functionality of that register

get_read_cmdmsg()[source]¶

Generate a message to do a readback (shortcut) command of the current register map

Returns:	A read UART command message
Return type:	list of `percival.carrier.txrx.TxMessage` objects

get_write_cmdmsg()[source]¶

Flatten the 2D matrix of datawords into one continuous list

Returns:	A write UART command message
Return type:	list of `percival.carrier.txrx.TxMessage` objects

`percival.carrier.txrx` module¶

Created on 4 Dec 2014

@author: Ulrik Pedersen

class percival.carrier.txrx.TxMessage(message, num_response_msg=1, expect_eom=False)[source]¶

Encapsulate a Percival carrier board message and the number of messages to expect in response

__init__(message, num_response_msg=1, expect_eom=False)[source]¶

TxMessage constructor

Parameters:	message (Byte array) – A Percival Carrier Board message contain address (2 bytes) and data (4 bytes) num_response_msg – Number of messages to expect in response expected_eom (boolean) – set true if end-of-message is expected in response

class percival.carrier.txrx.TxRx(fpga_addr, port=10001, timeout=2.0)[source]¶

Transmit and receive data and commands to/from the Carrier Board through the XPort Ethernet

__init__(fpga_addr, port=10001, timeout=2.0)[source]¶

TxRx Constructor

Parameters:	fpga_addr (string) – IP address or network name of the Carrier Board XPort device port (int) – IP port number timeout (floating point) – Socket communication timeout (seconds)

clean()[source]¶

Shutdown and close the socket safely

Sockets are normally closed down cleanly on exit from the interpreter, however this method may be used in case the socket need to be closed down temporarily.

rx_msg(expected_bytes=None)[source]¶

Receive messages of up to expected_bytes length

Raises RuntimeError:
Parameters:	expected_bytes – Number of bytes expected to be received. If expected_bytes is None, read at least one single message
	if a message of 0 bytes is received;indicating a broken socket connection
Returns:	The recieved message
Return type:	byte array

send_recv(msg, expected_bytes=None)[source]¶

Send msg and wait for receipt of expected_bytes in response or timeout

Parameters:	msg (Bytearray) – UART message to send
Returns:	Response from UART
Return type:	Bytearray

send_recv_message(message)[source]¶

Send a message and wait for response

Parameters:	message – a TxMessage object
Retuns:	Response from UART
Return type:	Bytearray

tx_msg(msg)[source]¶

Transmit a single message to the Carrier Board

Parameters:	msg (Bytearray of `percival.carrier.encoding.NUM_BYTES_PER_MSG` bytes) – Message to transmit

percival.carrier.txrx.TxRxContext(*args, **kwds)[source]¶

Provide a context which keeps a TxRx module alive with an open socket only for the duration of the context

Minimal example:

>>> msg = encode_message(0x0144, 0x00000000) # Header Info Readback
>>>
>>> # Start the context - create the TxRx object and open the socket
>>> with TxRxContext("192.168.1.3") as trx:
>>>     response = trx.send_recv(msg)
>>> # End of context - socket is closed down cleanly
>>> 
>>> response = decode_message(response)
>>> print response

`percival.carrier.encoding` module¶

Created on 4 Dec 2014

@author: Ulrik Pedersen

percival.carrier.encoding.END_OF_MESSAGE = b'\xff\xff\xab\xba\xba\xc1'¶: End of message is used in some cases. The EOM word is 0xFFFFABBABAC1

percival.carrier.encoding.NUM_BYTES_PER_MSG = 6¶: Number of bytes per message. Each message consist of a 2 byte address field and a 4 byte data field

percival.carrier.encoding.decode_message(msg)[source]¶

Decode a byte array into a list of (address, dataword) tuples.

The address field is a 16bit integer and the dataword is a 32bit integer.

Parameters:	msg (Bytearray) – The input message
Returns:	A list of (address, data) tuples

percival.carrier.encoding.encode_message(addr, word)[source]¶

Encode a single address and dataword into a bytearray.

Parameters:	addr – UART address (16bit integer) word – data word (32bit integer)
Returns:	bytearray of 6 bytes with address and dataword encoded

percival.carrier.encoding.encode_multi_message(start_addr, words)[source]¶

Encode multiple 32bit words as a multi-message.

Parameters:	start_addr – The UART starting address (a 16bit integer word) words – A list of 32bit integer words to be encoded
Returns:	A list of encoded words, each of which consists of 6 bytes: 2 words of address and 4 words of data

percival.carrier package¶

percival.carrier.devices module¶

percival.carrier.registers module¶

percival.carrier.txrx module¶

percival.carrier.encoding module¶

`percival.carrier` package¶

`percival.carrier.devices` module¶

`percival.carrier.registers` module¶

`percival.carrier.txrx` module¶

`percival.carrier.encoding` module¶