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PICBasic Pro and the PAK-VII
Here is code that works with a PAK-VII and PIC Basic Pro. The program just reads the TICK register and displays the second count on the serial port at 19200 baud.
For this example, I wrote "home made" shiftin and shiftout routines:
shiftoutput: ' sends iobyte output datapin for i=0 to 7 ' Set data pin to 0 or 1 low datapin if (iobyte & $80) <> $80 then goto so0 high datapin so0: iobyte=iobyte<<1 ' shift byte left pulsout clk,100 next return shiftinput: input datapin iobyte=0 for i=0 to 7 iobyte=iobyte<<1 ' shift left iobyte=iobyte | datap pulsout clk,100 next return
The rest of the code conversion was straightforward: adding the right defines, changing the nibble variables to bytes, and waiting for things to happen were all that was required.
' These are some starter routines ' that will help you use the PAK-7 ' Coprocessor from AWC Include "modedefs.bas" define LOADER_USED 1 ' comment this out if not using a boot loader Define OSC 20 DEFINE HSER_RCSTA 90h DEFINE HSER_TXSTA 20h DEFINE HSER_BAUD 19200 ' Change these to suit your setup datap var portc.2 ' Data pin (I/O) datapin var portc.2 clk var portc.3 ' Clk pin (output) ' Register names DURLOW con %000 DURHIGH con %001 RAWLOW con %010 RAWHIGH con %011 RISE con %100 FALL con %101 TICK200 con %110 TICK con %110 INP con %110 VER con %110 SUM con %111 i var byte iobyte var byte output clk output datap fpx var word ' Integer used by some routines fpb var byte ' byte ' parameters for FCommand chan var byte register var byte clearreg var bit clearchan var bit pause 5 ' wait for wake up gosub freset ' always reset! ' TEST CODE -- REPLACE WITH YOUR OWN t: gosub FTotalReset ' hard reset Fpx=0 gosub FPullup seconds var word last var word ' read time tloop: clearreg=0 clearchan=0 register=TICK chan=1 gosub FCommand seconds = fpx if last=seconds then tloop hserout [dec seconds,13,10] last=seconds goto tloop ' Reset the Pak7 I/O FReset: LOW DATAP LOW CLK pauseus 50 HIGH CLK pauseus 50 HIGH DATAP pauseus 50 LOW CLK pauseus 50 return FCommand: ' inputs chan = channel, register = register, clearreg and clearchan fpb=(clearchan<<7) + (clearreg<<6) + (register<<3) + chan gosub FSendByte FReadWord: pauseus 8 ' wait a bit for the result to be ready gosub shiftinput fpx.lowbyte=iobyte gosub shiftinput fpx.highbyte=iobyte return FTotalReset: fpb=$FF FSendByte: iobyte=fpb gosub shiftoutput return FReadByte: pauseus 8 gosub shiftinput fpb=iobyte return FPrescale: ' set fpb to the prescale constant fpb = fpb + $C0 goto FSendByte FPullUp: ' set fpx to the pull up mask fpb=%11010000 Fscmd: gosub FSendByte fpb=fpx goto FSendByte FThresh: ' set fpx to the threshold mask fpb=%11010001 goto Fscmd FSchmitt: ' set fpx to the Schmitt trigger mask fpb=%11010010 goto Fscmd pakclock con 3 ' 6us @ 20MHz (adjust for your clock) pakclocklow con 3 ' 3uS low 6uS + 3uS + 1uS hold = 10uS = 100kbps shiftoutput: ' sends iobyte output datapin for i=0 to 7 ' Set data pin to 0 or 1 low datapin if (iobyte & $80) <> $80 then goto so0 high datapin so0: iobyte=iobyte<<1 ' shift byte left pauseus pakclocklow pulsout clk,pakclock pauseus 1 next pauseus 50 ' give it some time to process return shiftinput: input datapin iobyte=0 for i=0 to 7 iobyte=iobyte<<1 ' shift left iobyte=iobyte | datap pauseus pakclocklow pulsout clk,pakclock pauseus 1 ' hold data a tick next return
