RB8506_Sifu Class Reference
[RB8506 SIFU]

#include <rb8506_sifu.h>

Inherits Pia.

List of all members.

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Detailed Description

Purpose

Provide digital inputs and outputs.

Description

Module RB8506, SIFU variant, is a digital input-output interface. It has four level-sensitive inputs, four negative-edge-sensitive inputs, four level outputs and four outputs that can be pulsed as a group.

There is also a provision to check if any of both the negative-edge-sensitive inputs and the level-sensitive inputs have changed state since it was last checked.

Inputs and outputs are available in TTL and in CMOS: TTL or CMOS can be selected with a switch on the front, two inputs or two outputs at the time. A LED indicates if TLL (red) or CMOS (green) is selected.

The SIFU module consists of a PIA parallel interface (see Pia) and a Sense Interrupt Flag Unit (SIFU) board.

The table below indicates which lines are pulse or level inputs-ouputs.

    line | kind of input-output
   ------+----------------------
      0  |  ]
      1  |  ] level
      2  |  ]
      3  |  ]
         |
      4  |  ]
      5  |  ] negative pulse
      6  |  ]           note 1
      7  |  ]
   

Note 1: contrary to what the hardware documentation states, I think that the pulse inputs are sensitive to a high-low transition.

When SIFU is created, its parallel interface (PIA) is configured as follows:

• the input port is read to clear any history
• the ouput port is set to zero

Usage

The class provides methods to read all inputs at a time or to read each input line individually. It also allows to check if any line has changed since the last time it was checked. Ouputs may be read or written all at once or each output may be read or written individually. Four pulse outputs can be pulsed at one time.

   RB8506_Sifu sifu( "sifu" );

   if ( sifu.inputLineHasChanged() )
   {
      sifu.setOuputPortData( sifu.getInputPortData() );
   }

Implementation

The following tables show how the SIFU input-output lines are connected to the PIA of the parallel interface.

    output line | PIA port A
   -------------+---------------------------------
       level 0  | PA0
             1  | PA1
             2  | PA2
             3  | PA3
                |
       pulse 4  | PA4  ]
             5  | PA5  ]
             6  | PA6  ] pulsed via CA2
             7  | PA7  ]
   

The pulse outputs are pulsed via control line CA2 (see enablePulseOutputs()).

     input line | PIA port B
   -------------+---------------------------------
       level 0  | PB4                      note 1
             1  | PB5
             2  | PB6
             3  | PB7
                |
       pulse 4  | PB0  ]
             5  | PB1  ] high-low transition
             6  | PB2  ]    recorded via CB1
             7  | PB3  ]                   note 2
   

Note 1: lines 0--3 connect to PB4--PB7 and that lines 4--7 connect to PB0--PB3.

Note 2: contrary to what the hardware documentation states, I think that CB1 must act on a high-low transistion.

Changes in one or more of the level inputs or a negative transition on one or more of the pulse inputs are recorded via CB1 (see isChangedInputLine()).

Public Member Functions
Construction
	~RB8506_Sifu ()
	destructor.
	RB8506_Sifu (NameCref name, Addr addr=DEF_ADDR, Rack rack=DEF_RACK)
	constructor.
Accessors
int	getInputPortData ()
	the input data bit-pattern; also clears input flip-flops.
int	getOutputPortData ()
	the bit-pattern of the outputs.
bool	isChangedInputLine ()
	true if the level of one or more input lines have changed; clears input-has-changed flag; see also tstInputLineLevel().
int	tstInputLineLevel (int line)
	the level of the specified input line; clears input-has-changed flag, retains state of input flip-flops; see also inputLineHasChanged(); may throw RulbusRangeError.
int	getInputLineLevel (int line)
	the level of the specified input line; clears input flip-flops; may throw RulbusRangeError.
int	getOutputLineLevel (int line)
	the line level of the specified output line; may throw RulbusRangeError.
bool	isEnabledPulseOutputs ()
	true if the pulse outputs are enabled.
Mutators
void	setOutputPortData (int data)
	set the outputs to the specified bit-pattern; may throw RulbusRangeError.
void	setOutputLineLevel (int line, bool set)
	set or clear specified output line; may throw RulbusRangeError.
void	enablePulseOutputs (bool enable=true)
	enable or disable the pulse outputs.
Static Public Attributes
Defaults
const Addr	DEF_ADDR = Pia::DEF_ADDR + 4
	default address (second PIA)
const int	DEF_DIRPA = 0xFF
	port A is output
const int	DEF_DIRPB = 0x00
	port B is input
const char	DEF_EDGECB1 = 'p'
	positive active edge
const char	DEF_DIRCA2 = 'o'
	CA2 output.
const char	DEF_DIRCB2 = 'o'
	CB2 output.
const char	DEF_LVLCA2 = 0
	CA2 0.
const char	DEF_LVLCB2 = 1
	CB2 1.
const bool	DEF_INTRCB1 = true
	enable CB1 interrupt flag
const int	DEF_OUTDATA = 0
	default output levels
Protected Member Functions
Construction and Assignment
	RB8506_Sifu ()
	prevent default construction
	RB8506_Sifu (RB8506_SifuCref rhs)
	prevent copying
RB8506_SifuRef	operator= (RB8506_SifuCref rhs)
	prevent copying
Tools
void	clearFlipFlops ()
	clear pulse input flip-flops.
Static Protected Member Functions
Class tools
int	swapNibbles (int byte)
	swap input data for line 0..3 with line 4..7.
int	swapLines (int line)
	swap input linenumber 0..3 with lne 4..7.

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The documentation for this class was generated from the following files:

• rb8506_sifu.h
• rb8506_sifu.cpp

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