Update specifications.md (#702)

* Update specifications.md

* Update specifications.md

Added note about considering check digit in available digit counts

Author: LanceMcCarthy

controls/barcode/specifications.md

@@ -10,19 +10,18 @@ position: 4
 
 # Specifications
 
-
-
-This help topic describes the specific characteristics of the bar codes per type.
+This help topic describes the specific characteristics of the barcodes per type.
 
 ## 
 
-
 | Barcode type | Character set | Length | Check digits |
 | ------ | ------ | ------ | ------ |
 |Code 128|ASCII (128 characters)|variable|Mod 103|
 |Code 39|[A-Z]; [0-9]; [ - . $ / + % ]|variable (avg. up to 20 chars)|optional (Mod. 43)|
-|EAN-13|numeric [0..9]|7 usable digits|1 check digit|
-|EAN-8|numeric [0..9]|12 digits|1 check digit|
+|EAN-13|numeric [0..9]|13 digits|1 check digit|
+|EAN-8|numeric [0..9]|8 digits|1 check digit|
 |Postnet|numeric [0..9]|variable|1 check digit|
 |UPC-A|numeric [0..9]|12 digits|1 check digit|
 |UPC-E|numeric [0..9]|7 digits|1 check digit|
+
+>note Be sure to take the check digit into consideration as it decreases the total number of usable digits for your data. For example, if you need 8 digits for your data; you can't use EAN-8 because 8 total digits, minus one check digit, leaves only 7 usable digits.