The documentation is pretty clear about how to calculate using the hmac algorithms: 

#!/usr/bin/perl
use warnings;
use strict;

use Digest::SHA qw(hmac_sha256_hex);

my $digest=hmac_sha256_hex("138539083512345apiKeyDEMO","apiSecretDEMO"
+);
print "Digest=$digest\n";

[download]

Update: output:

Digest=696e087f4b1902aa58d35e75b4600580d70a92ed68b23379373117fb3fe3064
+a

[download]

In reply to Re: Problems with HMAC SHA-256 by marto
in thread Problems with HMAC SHA-256 by agnome

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