I wouldn't try to store all the fields in individual scalars, but store them in an array like

@fields =  split /,/, $response, 39;
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Also, on a style-note, calling the fields $_r1, $_r2 etc doesn't really convey a lot of information about what the fields are (then again, maybe your real code does use names like

($date,$time,$type...) = ...
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)
You can use the following to name the fields in the array

use constant DATE => 0;
use constant TIME => 1;
use constant TYPE => 2;
...

my @fields = split /,/, $response, 39;

if ($fields[TYPE] eq 'widget') ...
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You could also use a hash -

my @fields = qw(date time type ...);
my %response;

@response{@fields} =  split /,/, $response, 39; # hash slice

if ($response{type} eq 'widget') {...
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