Hyundai GMS90X54C, GMS90X51C Timer/Counter 2 Operating Modes, P1.1 Remarks Input Clock, T2EX

GMS90X5XC Series HYUNDAI MicroElectronics

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 shown in Table 5.

Table 5. Timer/Counter 2 Operating Modes

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

Jan. 2001 Ver 1.0 19