What are the "Mercury Settings"?

This article describes the settings required for readers to when using Mercury Payment Systems (a.k.a Vantiv, Worldnet) as the backend processor. 

SecureMag family reader (SecureMag, SecureHead, SecureKey, Secure Moir, Spectrum Air):

The commands in this section will work for ITP Readers: SecureMag; SecureKey; SecureKey; BT Mag, UniMag Pro, Unimag II; UniMag II; Shuttle; BT Pay 200. You can run these commands in uDemo and other demos capable 

1. PIN Variant: DUKPT key management, using TDES with PIN Variant (not data)
   53 3E 01 5A (must be done prior to key injection)
2. Pre PAN 6: the first 6 digits of the PAN should be left in the clear (unmasked) 
   53 49  01 06  (sets pre-PAN to 6 and post-Pan is default to 4)
3. Show Expiration Date: the expiration date in the masked track2 data should be left in the clear (unmasked) for the masked track 2 data
   53 50 01 31
4. No LRC: turn show LRC off
   53 6F 01 30
5. Enhanced Format: Set the reader to ID TECH's Enhanced Encrypted Format (not Original Encrypted Format)
   53 85 01 31
   
   

MiniSmart II: (you can send these commands in the uDemo > Device > Send Data Command > Wrap NGA)

====== Set Pin Variant (MiniSmart II)======
CMD: 72 53 01 01 01 01

======Set Pre Pan 6, Post Pan 4======
CMD:72 53 01 20 02 06 04

======Set Pre Pan 6, Post Pan 4, Expiration Date no LRC in MSR equivalent in terminal settings (2c)======

CMD:7246020319005f3601029f1a0208409f3501219f33036028c89f4005f000f0a0019f1e085465726d696e616c9f150212349f160f3030303030303030303030303030309f1c0838373635343332319f4e2231303732312057616c6b65722053742e20437970726573732c204341202c5553412edf260101df1008656e667265737a68df110100df270100dfee150101dfee160100dfee170107dfee180180dfee1e08d0dc20d0c41e1400dfee1f0180dfee1b083030303135313030dfee20013cdfee21010adfee2203323c3cdfef4b037f0000