Stanford Research Systems SR620, Руководство пользователя

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Programming Examples 49
SR620 Universal Time Interval Counter
call DMA2 (seg,data,count,mode,status)
call StatCheck (address,status)
C get mode so we'll know which conversion factor to use
command (1:30) =' '
command (1:11) = 'MODE?;EXPD?'
call TxGpib (address,command)
call GetGpib (address,rstring)
read (rstring,101)tmode,dummy,texpd
C skip semicolon separator
101
format (I1,A,I1)
C
convert data and print both binary and converted form
call Convert (tmode,texpd,samples,data,fdata)
write (*,*)
write (*,*)'data'
do 20 i=0,samples-1
write (*,102)data(4*i+3),data(4*i+2),data(4*i+1),
+ data (4*i),fdata(i)
20 continue
102
format (1X,4Z4,' converted = ',D22.15)
goto
10
11 continue
end
C *******************************************************************
C converts the binary data to real numbers
subroutine Convert (tmode,texpd,samples,data,fdata)
integer*2
tmode,texpd,samples,data(0:19999),sign
integer*4 words(0:4)
real*8 fdata(0:4999)
real*8 factors(0:6)
C conversion factors
data
factors/1.05963812934D-14,1.05963812934D-14,
+ 1.05963812934D-14,1.24900090270331D-9,1.05963812934D-14,
+ 8.3819032D-8,.00390625/
do 10 i=0,samples-1
sign = 0
fdata(i) = 0.0D0
C get 8 data bytes
do 11 j=0,3
words(j) = data(4*i +j)
C get unsigned magnitude of word
if (words(j) .lt. 0)words(j) = 65536+words(j)
11 continue
C if answer less than 0 change sign and get magnitude
if (data(4*i+3) .lt. 0) then
sign = 1
do 12 j = 0,3
C take 1's complement of number