GMS90X5XC Series HYUNDAI MicroElectronics

Jan. 2001 Ver 1.0 19

TIMER 2

Timer 2 is a 16-bit timer/Counter with an up/down count feature. It can operate either as timer or as an event

counter which is selected by bit C/T2 (T2CON.1). It has three operating modes as show n in Table 5.

Note: ↓ = falling edge
Table 5. Timer/Counter 2 Operating Modes
Mode T2CON T2MOD T2CON P1.1/
T2EX Remarks Input Clock
RCLK or
TCLK CP/RL2 TR2 DCEN EXEN2 internal external
(P1.0/T2)
16-bit Auto-
Reload 0
0
0
0
0
0
0
0
1
1
1
1
0
0
1
1
0
1
X
X
X
↓
0
1
reload upon over-
flow
reload trigger (fall-
ing edge)
Down counting
Up counting
fOSC ÷ 12 Max.
fOSC ÷24
16-bit
Capture 0
0
1
1
1
1
X
X
0
1
X
↓
16 bit Timer/ Coun-
ter (only up-count-
ing)
capture TH2,TL2
→ RC2H,RC2L
fOSC ÷ 12 Max.
fOSC ÷ 24
Baud Rate
Generator 1
1
X
X
1
1
X
X
0
1
X
↓
no overflow
interrupt request
(TF2)
extra external inter-
rupt ("Timer 2")
fOSC ÷ 12 Max.
fOSC ÷ 24
Off X X 0 X X X Timer 2 stops - -