Revision History for Altair Floppy Disk Controller

C - 04/11/19
	- Include A14,A13 on the PROM address switch
	- Phantom* (when jumpered) disables RAM writes as well as reads
	- Move RAM DIP-switch to right to make room for an ejector style
	  50 pin header for the drive connector
	- Lower the 50 pin drive and 14 pin serial connectors away from
	  the top edge of the board

B - 10/28/14
	- Correctly label C21 (was C14)
	- Move S3, J2 slighly to right
	- Move 5v diagonal trace from underneath heat sink
	- Mark serial port as DCE instead of DTE
	- Increase hole size on J1 and J2 (floppy and serial port headers)
	- Run bus signal PINTE(28) to processor p58 through U16B OR gate and
	  resistor divider.
	- Buffer pDBIN with U11C and use buffered signal for U13C and U12C
	- Add U13D to qualify (AND) sINP with buffered pDBIN into U15A 

A - 10/03/14, Prototype