the need for speed

george miyagi · 2005-07-24 16:20

hi
i am controlling 6 daisy-chained max7219s, via an external application, written in Processing. The thing is, the data coming in is comnig in really slowly. Would appreciate it if anyone had any ideas as to why?

Could it be because i'm sending 2 wait strings (the "*"'s)? But without them it doesn't seem to work.
also, i have tried sending other data than binary to the BS, but can't seem to get it to work....

here's the code:


progPin CON 16 ' The programming PIN
ledCmd VAR BYTE
serStr VAR BYTE(10)

Clock         CON 0                                      ' shift clock to MAX7219
DPin          CON 1                                      ' shift data to MAX7219
Load          CON 2                                      '


'======Constants==========================

Decode        CON $09                                    ' bcd decode
Intensity     CON $0A                                    ' brightness
Scan          CON $0B                                    ' scan (column) limit
ShutDn        CON $0C                                    ' shutdown (1 = on)
Test          CON $0F                                    ' display test mode

Yes           CON 1
No            CON 0


'==========Variables=========================

index         VAR NIB                                    ' loop counter
idxOdd        VAR index.BIT0                             ' is index odd? (1 = yes)
d7219         VAR BYTE                                   ' data for MAX7219
char          VAR BYTE                                   ' character ee address
col           VAR NIB                                    ' column value
row           VAR NIB                                    ' row value
a       VAR WORD                                   ' ee pointer
b       VAR BYTE
' Baud          CON 16468
 Baud          CON 84
 ' Baud          CON 32

'=====EEPROM Data=============================

'=========Initialization======================================
'++++++This is edited code++++
'++++ LOOKUP index,[noparse][[/noparse]Scan,7,Intensity,7,ShutDn,1],d7219 +++++
'===============================================================
LOW Load
Initialize:
  DIRL = %111                                            ' clock, data and load pins
 FOR index = 0 TO 5
    LOOKUP index,[noparse][[/noparse]Scan,7,Intensity,7,ShutDn,1],d7219
    SHIFTOUT Dpin,Clock,MSBFIRST,[noparse][[/noparse]d7219]
    IF idxOdd = No THEN NoLoad
    PULSOUT Load,3                                       ' load parameter
  NoLoad:
  NEXT
'==========Clear buffers========================================

'===============================================================
'DATA 

Main:

get_Data:

      FOR col = 1 TO 8

SERIN progPin, Baud, [noparse][[/noparse]WAIT ("*"),  BIN serStr(0), BIN serStr(1), BIN serStr(2), BIN serStr(3), BIN serStr(4), BIN serStr(5)] ' wait for Comm
FOR b=0 TO 5
SHIFTOUT Dpin,Clock,MSBFIRST,[noparse][[/noparse]col, serStr(b)]
NEXT
        PULSOUT Load,3
SEROUT progPin, Baud,  ' SEND the serial DATA

      NEXT



GOTO Main
'================================================================

and here's a snipped from processing:

for (row=0;row<8;row++){
print (row);
 for (matrix=5;matrix>-1;matrix--){ 
delay(40);
output =  (picData[noparse][[/noparse]matrix][noparse][[/noparse]row]);
myPort.write("*");
myPort.write(output);
myPort.write("*");
 }

}
}

Post Edited (george miyagi) : 7/24/2005 4:47:48 PM GMT

Bean · 2005-07-24 16:34

Why are you sending a "*" after the data ? That could get the receiver out-of-sync.
Bean.

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·

george miyagi · 2005-07-24 17:01

I'm not sure (and can't really remember how i came to the conclusion to put it in) , but without it, it doesn't work. ie. my data comes through garbled.
++++++++

Ammendment:
Hold, that i got it to work without the extra "*" but am still somewhat lacking in speed? how about shifting 16 bits at a time through the serial?

Post Edited (george miyagi) : 7/25/2005 6:03:44 AM GMT

the need for speed

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