1  /*******************************************************************************
 2  
 3  EMC2 HAL component to implement Multistate toggle switch
 4  Authors ArcEye 15122011 schooner30@tiscali.co.uk / Andy Pugh andy@bodgesoc.org
 5  License GPL
 6  Copyright 2011 
 7  
 8  example Hal linkages required:-
 9  ################################
10  loadrt multiswitch cfg=4,6,8
11  addf multiswitch.0 servo-thread
12  ...
13  net toggle-switch multiswitch.0.toggle <= parport.N.pin-nn-out
14  net state1 multiswitch.0.state1 => parport.N.pin-nn-in
15  net state1 multiswitch.0.state2 => parport.N.pin-nn-in
16  net state1 multiswitch.0.state3 => parport.N.pin-nn-in
17  
18  If you require an "all off" state, then make the component one bit oversize and
19  don't connect the extra pin. 
20  
21  *******************************************************************************/
22  
23  component multiswitch           """This component toggles between a specified number of output bits""";
24  
25  pin in bit up = false           "Receives signal to toggle up";
26  pin in bit down = false         "Receives signal to toggle down";
27  
28  param rw unsigned top-position  "Number of positions";
29  param rw signed position      "Current state (may be set in the HAL)";
30  
31  pin out bit bit-##[32:personality] = false       "Output bits";
32  
33  modparam dummy cfg              """cfg should be a comma-separated list of sizes
34  for example cfg=2,4,6 would create 3 instances of 2, 4 and 6 bits respectively.
35   Ignore the "personality" parameter, that is auto-generated""";
36  
37  function _ ;
38  option extra_setup yes;
39  option count_function yes;
40  
41  variable int old_up = 0;
42  variable int old_down = 0;
43  
44  author "ArcEye schooner30@tiscali.co.uk / Andy Pugh andy@bodgesoc.org";
45  license "GPL";
46  ;;
47  
48  #define MAX_COUNT 32
49  int cfg[MAX_COUNT];
50  RTAPI_MP_ARRAY_INT(cfg, MAX_COUNT, "array of function sizes");
51  
52  FUNCTION(_) {
53      int i;
54      
55      // debounce
56      if (up && !old_up) { position++; }
57      if (down && !old_down) { position--;}
58      old_up = up;
59      old_down = down;
60      
61      if (position < 0) position = top_position;
62      if (position > top_position) position = 0;
63      
64      for (i = 0 ; i < personality; i++){
65          bit(i) = (i == position);
66      }
67  
68  }
69  
70  EXTRA_SETUP(){
71      personality = cfg[extra_arg];
72      top_position = personality - 1;
73      return 0;
74  }
75  
76  int get_count(void){
77      int i;
78      for (i=0; cfg[i] != 0 && i < MAX_COUNT; i++){}
79      if (i == 0){
80          cfg[0] = 4;
81          i = 1;
82      }
83      return i;
84  }
85