Remote Processing BASIC 52 - Manual (Page 152)

RPBASIC-52 PROGRAMMING GUIDE
B-3
20 string 1000,50:rem 20 strings, 50 bytes
30 dim flag(15)
:rem flags for main task dispatcher
40 okflg = 0 :rem OK received flag
50 ontick 1,1000 :rem communication watchdog and system timer
60 on com$ 1,49,13,2000 :rem interrupt on 49 chars or
70 ctim = 10
:rem communication timeout if on line.
80 $(2) = "NO CARRIER" :rem string constant
90 nocfg = 0
:rem no carrier flag
100 htim = 0
110 clear com(1) :rem get rid of any previous stuff
rem Send reset to modem
rem NOTE: If you are allowing for downloads to the card,
rem skip around line 150. This can be done by
rem checking for a flag set in expanded memory (segment 1)
rem If it is set, then don't do card reset.
150 cycle = 4 :rem do modem reset
rem other initialization as needed by the program
rem Main program loop
rem This is a multi-tasker dispatcher. It performs various tasks
rem as dictated by other interrupts or programs
rem the array FLAG is used to indicate a process should be performed
rem For this example
rem flag(0) = send back analog input channel 0 value
rem flag(1) = send back digital 0 value
rem flag(2) = hang up
rem flag(3) through flag(14) are used for other process functions
rem for this example, only the first 11 flags are processed.
200 for mcycl = 0 to 14
210 if flag(mcycl) = 0 then 300
:rem when a 1, then do a process
220 if mcycl > 5 then 250
rem mcycl = 0 1 2 3 4 5
230 on mcycl gosub 10000,11000,12000,13000,14000,15000
240 goto 300
rem mcycl = 6 7 8 9 10
250 on mcycl-6 gosub 16000,17000,18000,19000,20000
260 goto 300
rem do mcycl 11-14 or more here
300 next
rem DEBUG
400 print "cycle =",cycle," atim =",atim,cr,
rem if there are other tasks that have to be done, then do them here
500 goto 200
rem ONTICK processing
rem Communication timeouts checked
rem if on line, some communication must be received in 10 seconds
rem Exception processing is: Hang up (waits 3 seconds)
rem Long data send (ctim set longer)
rem If you need to do other things, then add them as needed.
rem Gosub to routine based on current cycle
rem Cycles are:
rem 0 = waiting for RING 1400
rem 1 = looking for CONNECT 1500