AT&T 6300 Keyboard Controller

Greetings, all! System in Question: AT&T 6300 I have two of these systems and was going through them, taking the best parts of the one and putting them in the other to build out a good machine. I happened upon a difference between the two that I can't figure out what I've stumbled upon. The keyboard controller for the 6300 is either an 8041 or 8741 chip, as defined by the service manual. The one machine has an 8041A chip, so that's normal. The other machine doesn't have a chip at all. Instead, it has a piggyback card in that slot where the IC is supposed to be. The piggyback card has a chip on it that LOOKS to be a 88414 chip. I'll write below all the relevant numbers on the card. There is a wire that goes from the board around to the topside of the logic board as well. Not sure where it connects, I haven't pulled the logic board completely up yet. Anyone have an idea of what this might be and if so, documentation and/or description of benefits? Thanks for your help! Tarsi 210 List of Relevant Numbers: - On the main chip, it has 88414 plus a adhesive tag that someone had written on it "PDBD". - The board itself is stamped: 491230 Z MI293 NA 6/84 (the last the date, I presume) Also on the board is: MI293 COD.49199P-E-E4 - Yet another chip has the number: TMS7000NL-2 -- ---------------------------------------------- Homepage: http://tarsi.binhost.com binHOST.com: http://www.binhost.com Forever Beyond: http://www.foreverbeyond.org ----------------------------------------------