sEcTl0N |
. I NTRODUCT
I ON
I
.
I
GENERAL DESCR
I PT I
ON
AND PURPOSE
Campbel
I Sclenflflcts
C20
CASSETTE
INTERFACE
al lows the
users of
CS I
rs
data
I
oggers
to retr I
eve
data
stored
on tape.
I tts
ma
I n
purpos€
ls
to
read tapes
g€nerated
by
fhe
CR5, CR21,
or
CR7
dataloggers, decode the format,
and
fransmlt the
data
ln a
usable
form
fo
your
computer,
modem,
fermlnal,
prlnter,
or any
other
equlpmenf thaf
can communlcafe
vla
the
standard
RS252
lnferface.
The
C20 ls
deslgned
for slmple
operatlon
yet
lncludes
the
flexlblllty
fo lnferface rlth most
of the
broad range of
compufers
and
communlcatlon
equlpment aval
lable today. Hardrare
trhandshaklngn
(for
example,
uslng such I lnes
as
rclear
to sendn
or
tdafa
termlnal
readyi)
through fro Independent RS252
porfs
allors the
user to Interface hls
tape
recorder
rlth elfher
data
communlcaflon
tyPe equlpment
(DCE)
such
as compufers and modems
or rlth data fermlnal type
egulpment
(DTE)
such as fernlnals or
prlnfers,
or rlth
both
types
of equlpnent
sfmultaneously.
Addlflonal
ly,
rsoftrare
hcndshaklngr
such
as
slngle
byte commands
to
nstopln, nsend
one llne
of daian
or
nsend
data
contlnuouslyr
makes
communlcatlon
sfralght forrard.
Such
profocol
ls
us€r
programmable
lf fhe
default
protocol
ls
lncompaflble
rlfh
your
parf
I cu
I
ar
equ
I
pment.
The
C20
CASSETTE
INTERFACE
reads
Campbel
I Sclentlflcts ner
hlgh
denslty,
hlgh
speed,
hlgh
rellablllty
tape
formaf, Formaf
ll.
For
6xample,
180r000 lor r€solutlon data
polnfs
as
opposed to
81000
can
nor
be stored on a slngle slde
of a 60
mlnufe
cassette
tape
(30
mlnufes/slde).
At
fhe 9600 bft
p€r
second
(baud)
rafe
the C20
reads,
decodes
and
oufputs
the
data
at
a
rate
of
100
datapofnts
p€r
second
(100
data
polnts
..
1000
ASCI
I characfers
=
10,000
blts). The C20
can
also be srltched
to
read fapes rrltien
ln
the
orlg Inal
fornat,
Format
l.
The neu
format
Incorporates
a unlque error
defectlon and
correct
I
on
process
that
greaf
I
y
I mproves
dafa
I
ntegr I
ty
and
mlnlmlzes the
problens
arlslng from damaged
tapes.
For
example,
a
tburst
errorn
that rlpes
ouf up
fo 16
adJacenf dafapolnfs
on
tape wlll be
corrected by the
C20
rlth no
loss of data. The
errot: correctlng
scheme ls
also opflmlzed
fo
correcf
randomly
d I
spersed
errors.
Dafa
rrlffen
to
fape by CSI
dafaloggers
uslng fhe
ner
formaf
can
be
read and
output
by
fhe
C20 In elther of
tro dlfferent
forms:
(l)
as
ten-byte
ASCII dafa
values or Q) as fro-byfe
or
four-byte
blnary data
values.
Appendlx
B descrlbes ln
detall
fhe
dafa
t-l