$DC0F/56335/CIA1+15:  Control Register B

   +----------+-----------------------------------------------------+
   | Bit  7   |   Set Alarm/TOD-Clock: 1 = Alarm, 0 = Clock         |
   | Bits 6-5 |   Timer B Mode Select:                              |
   |          |            00 = Count System 02 Clock Pulses        |
   |          |            01 = Count Positive CNT Transitions      |
   |          |            10 = Count Timer A Underflow Pulses      |
   |          |            11 = Count Timer A Underflows While CNT  |
   | Bit  4   |   Force Load Timer B: 1 = Yes                       |
   | Bit  3   |   Timer B Run Mode: 1 = One-Shot, 0 = Continuous    |
   | Bit  2   |   Timer B Output Mode to PB7: 1 = Toggle, 0 = Pulse |
   | Bit  1   |   Timer B Output on PB7: 1 = Yes, 0 = No            |
   | Bit  0   |   Start/Stop Timer B: 1 = Start, 0 = Stop           |
   +----------+-----------------------------------------------------+

   Default Value: $08/8 (%00001000)

Kernal-Reference:

 STA $DC0F   : $ED99 $EE27 $F882 $F945 $FBBC $FDB6