Class: PCANUSB

Inherits:
Object
  • Object
show all
Defined in:
lib/pcanusb.rb

Defined Under Namespace

Modules: Core

Constant Summary collapse

BAUD_1M =

BAUD rates used by “init”

0x0014
BAUD_500K = 
0x001C
BAUD_250K = 
0x011C
BAUD_125K = 
0x031C
BAUD_100K = 
0x432F
BAUD_50K = 
0x472F
BAUD_20K = 
0x532F
BAUD_10K = 
0x672F
BAUD_5K = 
0x7F7F
CAN_INIT_TYPE_ST =

used by “init” and “set_receive_filter”

0
CAN_INIT_TYPE_EX =

11 Bit-ID handling - Standard frame

1
MSGTYPE_STANDARD =

used by “write” and “read”

0x00
MSGTYPE_RTR = 
0x01
MSGTYPE_EXTENDED = 
0x02
MSGTYPE_STATUS = 
0x80
CAN_OK =

return values

0x0000
CAN_XMTFULL =

No error.

0x0001
CAN_OVERRUN =

Transmission buffer of the controller is full.

0x0002
CAN_BUSLIGHT =

CAN controller has been read out too late.

0x0004
CAN_BUSHEAVY =

Bus error: An error counter has reached the ‘Light’ limit.

0x0008
CAN_BUSOFF =

Bus error: An error counter has reached the ‘Heavy’ limit.

0x0010
CAN_QRCVEMPTY =

Bus error:Actual state from the CAN controller is ‘Bus Off’.

0x0020
CAN_QOVERRUN =

Receive queue is empty.

0x0040
CAN_QXMTFULL =

Receive queue has been read out too late.

0x0080
CAN_REGTEST =

Transmission queue is full.

0x0100
CAN_NOVXD =

Register test of the 82C200/SJA1000 has failed.

0x0200
CAN_ILLHW =

Driver is not loaded.

0x1400
CAN_ILLNET =

Hardware handle is invalid.

0x1800
CAN_MASK_ILLHANDLE =

Net handle is invalid.

0x1C00
CAN_ILLCLIENT =

Mask for all handle errors.

0x1C00
CAN_RESOURCE =

Client handle is invalid.

0x2000
CAN_ILLPARAMTYPE =

Resource (FIFO, client, timeout) cannot be created.

0x4000
CAN_ILLPARAMVAL =

Parameter is not permitted/applicable here.

0x8000

Class Method Summary collapse

Class Method Details

.close ⇒ Object

Close the PCAN device connection.



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# File 'lib/pcanusb.rb', line 66

def self.close
  return Core::cAN_Close
end

.get_usb_device_number ⇒ Object

Return the device number associated with the connected PCAN.



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# File 'lib/pcanusb.rb', line 137

def self.get_usb_device_number
  number = Core::Device_Number.malloc
  
  err = Core::getUSBDeviceNr(number)
  
  return err, number.value
end

.init(baud_value, message_type = CAN_INIT_TYPE_EX) ⇒ Object

Initialize the PCAN device with a BAUD rate and message type. Valid message types are

  • CAN_INIT_TYPE_ST

    Standard format IDs

  • CAN_INIT_TYPE_EX

    Extended IDs



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# File 'lib/pcanusb.rb', line 56

def self.init(baud_value, message_type = CAN_INIT_TYPE_EX)
  err = Core::cAN_Init(baud_value, message_type)
  
  # allow the hardware to initialize
  sleep 0.125
  
  return err
end

.read ⇒ Object

Read one CAN message from the PCAN FIFO. Returns the error code, message type, ID and data array.



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# File 'lib/pcanusb.rb', line 97

def self.read
  message = Core::TPCANMsg.malloc
  
  err = Core::cAN_Read(message)
  
  return err, message.message_type, message.id, message.data[0..message.length - 1]
end

.read_id(id, timeout = 1) ⇒ Object

Read a message with a given ID. Returns the received data array if the required ID is received within the timeout or false if not.



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# File 'lib/pcanusb.rb', line 107

def self.read_id(id, timeout=1)
  read_timeout = Time.now + timeout

  begin
    err, rx_type, rx_id, rx_data = self.read

    if err == CAN_OK && rx_id == id then
      return rx_data
    end
  end while Time.now < read_timeout
  
  return false
end

.reset_client ⇒ Object

Reset the PCAN device.



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# File 'lib/pcanusb.rb', line 122

def self.reset_client
  return Core::cAN_ResetClient
end

.set_receive_filter(fromID, toID, message_type = MSGTYPE_EXTENDED) ⇒ Object

Set the range of message ID that will be accepted. CAN_ResetFilter is used first to close the filter range, then CAN_MsgFilter is used to open it up.



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# File 'lib/pcanusb.rb', line 90

def self.set_receive_filter(fromID, toID, message_type = MSGTYPE_EXTENDED)
  Core::cAN_ResetFilter
  return Core::cAN_MsgFilter(fromID, toID, message_type)
end

.status ⇒ Object

Retrieve the current PCAN status.



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# File 'lib/pcanusb.rb', line 71

def self.status
  return Core::cAN_Status
end

.version_info ⇒ Object

Provide information about the PCAN.



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# File 'lib/pcanusb.rb', line 127

def self.version_info
  info = Core::Version_Info.malloc
  
  err = Core::cAN_VersionInfo(info)

  # info.value is an array of characters, convert it to string 
  return info.value.pack("c128")
end

.write(id, data, message_type = MSGTYPE_EXTENDED) ⇒ Object

Initiates a transmission of a CAN message with a given ID. the data parameter is expected to be less than 8 bytes.



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# File 'lib/pcanusb.rb', line 77

def self.write(id, data, message_type = MSGTYPE_EXTENDED)
  message = Core::TPCANMsg.malloc
  message.id = id
  message.message_type = message_type
  message.length = data.length
  message.data = data.dup
  
  return Core::cAN_Write(message)
end