S3P7588X Datasheet, PDF (271/326 Pages) Samsung semiconductor – 4-BIT RISC MICROPROCESSOR

TIMERS and TIMER/COUNTERS
S3P7588X
TC EVENT COUNTER FUNCTION
Timer/counters can monitor or detect system 'events' by using the external clock input at the TCLn pin as the
counter source. The TC mode register selects rising or falling edge detection for incoming clock signals. The
counter register is incremented each time the selected state transition of the external clock signal occurs.
With the exception of the different TMODn.4–TMODn.6 settings, the operation sequence for TC's event counter
function is identical to its programmable timer/counter function. To activate the TC event counter function,
— Set TMODn.2 to "1" to enable TC;
— Clear TMODn.6 to "0" to select the external clock source at the TCLn pin;
— Select TCLn edge detection for rising or falling signal edges by loading the appropriate values to TMODn.5
and TMODn.4.
— P3.0 and P3.1 must be set to input mode.
TMODn.5
0
0
Table 12-5. TMODn Settings for TCLn Edge Detection
TMODn.4
0
1
Rising edges
Falling edges
TCLn Edge Detection
12-14