P9842AB chip data sheet or identification
As noted, this is a 


  CD4528BCN Dual Monostable Multivibrator


If you cannot find this (originally by RCA labs), then to convert to the On Semi equivalent number, do this:

New number = MC1 + numeric value (in this case 4528). There may or may not have been a part made, but in most cases On Semi (as Motorola semiconductor products sector) would have done so at some point.

For MC14528 we can actually find a datasheet.