Field Change Notice FCN2-004
August 12, 1982
Effectivity: Chroma, Model 2103, Serial Numbers 0011 through 0106, 0108 through 0113, 0116, 0121, 0125, 0132, 0138, 0139, 0141, 0149 through 0151.
Reason for Change: To provide computer access to end of conversion from A/D converter. This prevents the Chroma from mysteriously changing its own parameter, modifying programs, switching selections, tapping the tapper, etc.
Material Required: EOC Modification kit (PL30-7226401), set of eight REv. 12 ROMs.
Parts Kit: Order KFC2-004.
Install the EOC Modification P.C. assembly on I/O Board as shown by the printed circuit components drawing. Take care to observe proper orientation as the 4 pins can be reversed and still fit into the feedthroughs. Remove (8) ROMs Z29 through Z36 from the Computer Board and replace them with the Rev. 12 ROMs being certain to install them in their correct order. ROM C0=Z29, C8=Z30, D0=Z31, D8=Z32, E0=Z33, E8=Z34, F0=Z35 and F8=Z36. When finished perform the following checkout:
- Set the Chroma on a normal program (make sure program modified light is off, located on large display).
- Momentarily short Z3, Pin 22 to ground (on I/O Board). Be careful not to hit any other pins.
- Check large display to see if program modified light is still off, if it is off all is OK, if not, check wiring.
Rhodes Chroma National Service Manager