Source code for spinnman.messages.scp.impl.read_fpga_register
# Copyright (c) 2015 The University of Manchester
#
# Licensed under the Apache License, Version 2.0 (the "License");
# you may not use this file except in compliance with the License.
# You may obtain a copy of the License at
#
# https://www.apache.org/licenses/LICENSE-2.0
#
# Unless required by applicable law or agreed to in writing, software
# distributed under the License is distributed on an "AS IS" BASIS,
# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
# See the License for the specific language governing permissions and
# limitations under the License.
import struct
from spinn_utilities.overrides import overrides
from spinnman.messages.scp.abstract_messages import (
AbstractSCPRequest, AbstractSCPResponse, BMPRequest, BMPResponse)
from spinnman.messages.scp.enums import SCPCommand, SCPResult
from spinnman.messages.scp import SCPRequestHeader
from spinnman.exceptions import SpinnmanUnexpectedResponseCodeException
_ONE_WORD = struct.Struct("<I")
[docs]class ReadFPGARegister(BMPRequest):
"""
Requests the data from a FPGA's register.
"""
__slots__ = []
def __init__(self, fpga_num, register, board):
"""
Sets up a read FPGA register request.
:param int fpga_num: FPGA number (0, 1 or 2) to communicate with.
:param int register:
Register address to read to (will be rounded down to
the nearest 32-bit word boundary).
:param int board: which board to request the FPGA register from
"""
# check to stop people asking for non-word aligned memory addresses
# inverses all bits of a value, so is basically a inverse mask for the
# value entered.
arg1 = register & (~0x3)
super().__init__(
board,
SCPRequestHeader(command=SCPCommand.CMD_LINK_READ),
argument_1=arg1, argument_2=4, argument_3=fpga_num)
[docs] @overrides(AbstractSCPRequest.get_scp_response)
def get_scp_response(self):
return _SCPReadFPGARegisterResponse()
class _SCPReadFPGARegisterResponse(BMPResponse):
"""
An SCP response to a request for the version of software running.
"""
__slots__ = [
"_fpga_register"]
def __init__(self):
super().__init__()
self._fpga_register = None
@overrides(AbstractSCPResponse.read_data_bytestring)
def read_data_bytestring(self, data, offset):
result = self.scp_response_header.result
if result != SCPResult.RC_OK:
raise SpinnmanUnexpectedResponseCodeException(
"Read FPGA register", "CMD_LINK_READ", result.name)
self._fpga_register = _ONE_WORD.unpack_from(data, offset)[0]
@property
def fpga_register(self):
"""
The register information received.
:rtype: int
"""
return self._fpga_register