6172 CAN Micro Controller Module AN004

This application example is not yet completely tested

64 bit digital output with CD 4094

This application example enables the user to use 64 CMOS digital outputs.

Eight pieces CD 4094 are used for this example. These standard CMOS devices can deliver a maximum of 1mA per output.

This example uses the maximum capacity of one CANopen PDO, it can easily be expanded to 256 outputs, using 4 PDO's.

        header  "64 digital outputs AN004"
 
outputs:equ     32              ;64 outputs memory location (8 bytes)
 
enable: equ     7               ;output enable of 4094's (OUT8)
strobe: equ     3               ;strobe of 4094's (OUT4)
 
;initialization sequence 
 
        sequence seq_0 
 
        resa    enable          ;output enable inactive
        resa    strobe          ;strobe inactive
        shspd   1               ;SPI shifter at 1.1 µS/bit 
        shpat   0               ;normal data, no shifted clock 
        srdy                    ;READY output active 
        
        call    seq_3           ;write memory location 32-39 to 4094's
        
        seta    enable          ;enable outputs
        enasq   0               ;enable sequences
        endsq
 
;write memory location 32..39 to 4094's
 
        sequence seq_3,,outputs+7 ;start on write of location 39
        
        shom    outputs+7         ;first outputs 57-64
        shom    outputs+6         ;      outputs 49-56
        shom    outputs+5     
        shom    outputs+4     
        shom    outputs+3     
        shom    outputs+2     
        shom    outputs+1         ;      outputs 9-16
        shom    outputs           ;      outputs 1-8
        
        seta    strobe            ;STROBE high for 7 µS
        resa    strobe          
 
        endsq
        
        end

Assuming that all 6172 objects are in their default state, the following objects need to be adjusted (if a PDO is used):

 

Index	Subindex	Value	Description
1600h	0	2	2 objects in receive PDO 1
1600h	1	63200920h	memory location 32-35
1600h	2	63200A20h	memory location 36-39

The 64 digital outputs now can be set by:

• sending PDO 1 to the 6172
  (108 bits message)
• writing object 6320h, subindex 8 and 9, using two SDO writes
  (4 x 108 bits messages)
• writing object 6200h, subindex 33-40, using eight SDO writes
  (16 x 108 bits messages)

Copy and Paste this part direct after the declarations in the canappl.bas program
this program can be found on the 6197 designers kit diskette or
ordered separately as service part together with one of our CAN products.  

APPLICATION:
 
'This simple program is made for one 6172 and a 6390 as CAN bus interface
'the following assumptions are done:
'- 6390 is connected to COM2
'- 6172 ID = 1, CANbus speed = 50 kBAUD
'- assembled sequence file is "AN004.seq"
 
'the 64 digital output values are stored in the DIG% table
'all digital outputs are randomly set to 1 or 0 and then 
'send to the 6172 (via one PDO)
'this continues until the user presses enter
 
DIM DIG%(64)
RANDOMIZE (-TIMER)
 
CLS
PRINT "CD Systems 6172 AN004 DEMO program"
PRINT
 
Activate6390 2, 19200                          '6390 works at COM2, 19200 BAUD
SetCANBUSSpeed 50                                         'CAN BUS at 50 kBAUD
 
C% = CheckSequence%(1, "AN004.seq")     'download sequence if not already done
 
C% = PutU8% (1, &h1600, 0, 2)           '2 objects in receive PDO1
C% = PutU32% (1, &h1600, 1, &h63200920) 'receive PDO1 to memory 32-35
C% = PutU32% (1, &h1600, 2, &h63200A20) 'receive PDO1 to memory 36-39
 
SendNMTCommand (1, 1)                   'node in operational state
 
DO
 ' random values to DIG% and print them
 
  LOCATE 10, 1
 
  FOR I% = 1 TO 64
    DIG%(I%) = CINT(RND(1))
    PRINT HEX$(DIG%(I%));
  NEXT
 
 ' accumulate 64 digital values into 8 byte string
  PDO$ = ""
  FOR I% = 1 to 56 step 8: P% = 0: B% = 0
   FOR J% = 1 to 8
    IF DIG% (I% + J% - 1) = 1 then P% = P% + B%
    B% = B% * 2
   NEXT J%
   PDO$ = PDO$ + CHR$(P%)
  NEXT I%
 
 ' send PDO to 6172
  PDOCOB% = (1 + 512) * 32                           'rx PDO1 COB ID 
  SendToCAN (CANIDS$ (PDOCOB% + 8) + PDO$)
 
  R$ = ReceiveFromCAN$                       'ignore any CAN message
 
LOOP UNTIL INKEY$ = CHR$(13)
 
SendNMTCommand (1, 2)                             'stop node
 
 
END