DS80C390_00 Datasheet, PDF (110/155 Pages) Dallas Semiconductor – High-Speed Microcontroller User’s Guide Supplement

DS80C390 High-Speed Microcontroller User’s Guide Supplement
Divide by 13 option
The other change to the timers associated with the DS80C390 is the inclusion of a divide by 13 option for
Timer 1 and Timer 2. The option in independently enabled for each timer by setting the D13T1 (for timer
1) or D13T2 (for timer 2) bits. When enabled by setting the appropriate bits, the timer input from the T1
or T2 external pins will be replaced by a timebase that is OSC/13. The following figure illustrates the
operation of these bits.
T1 = P3.5
(T2 = P1.0)
To C/T selector
As shown in High-Speed Microcontroller User's Guide
T1 = P3.5
(T2 = P1.0)
OSC / 13
INPUT
D13T1 = T2MOD.4
(D13T2 = T2MOD.3)
0
To C/T selector
1
As implemented in DS80C390 with divide by 13 option
The setting of the divide by 13 bits will affect all operations of timer 1 and all operations of timer except
baud rate generator mode. The baud rate generator mode of Timer 2 will not be affected by any setting of
the D13T2 bit.
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