TS87C51RB2-LIA Atmel, TS87C51RB2-LIA Datasheet - Page 19

• Manufacturer Part Number: TS87C51RB2-LIA
• Description: IC MCU 8BIT 16K OTP 30MHZ 40-DIP
• Manufacturer: Atmel
• Series: 87Cr

Specifications of TS87C51RB2-LIA

• Core Processor: 8051
• Core Size: 8-Bit
• Speed: 30/20MHz
• Connectivity: UART/USART
• Peripherals: POR, PWM, WDT
• Number Of I /o: 32
• Program Memory Size: 16KB (16K x 8)
• Program Memory Type: OTP
• Ram Size: 512 x 8
• Voltage - Supply (vcc/vdd): 2.7 V ~ 5.5 V
• Oscillator Type: Internal
• Operating Temperature: -40°C ~ 85°C
• Package / Case: 40-DIP (0.600", 15.24mm)
• Lead Free Status / RoHS Status: Contains lead / RoHS non-compliant
• Eeprom Size: -
• Data Converters: -

6.4.2. Programmable Clock-Output
In the clock-out mode, timer 2 operates as a 50%-duty-cycle, programmable clock generator (See Figure 6) . The
input clock increments TL2 at frequency F
At overflow, the contents of RCAP2H and RCAP2L registers are loaded into TH2 and TL2. In this mode, timer
2 overflows do not generate interrupts. The formula gives the clock-out frequency as a function of the system
oscillator frequency and the value in the RCAP2H and RCAP2L registers :
For a 16 MHz system clock, timer 2 has a programmable frequency range of 61 Hz
(F
Timer 2 is programmed for the clock-out mode as follows:
Rev. C - 06 March, 2001
OSC
Set T2OE bit in T2MOD register.
Clear C/T2 bit in T2CON register.
Determine the 16-bit reload value from the formula and enter it in RCAP2H/RCAP2L registers.
Enter a 16-bit initial value in timer registers TH2/TL2. It can be the same as the reload value or a different
one depending on the application.
To start the timer, set TR2 run control bit in T2CON register.
/2
16)
to 4 MHz (F
XTAL1
Clock OutFrequency
F
OSC
Figure 5. Auto-Reload Mode Up/Down Counter (DCEN = 1)
XTAL
/4). The generated clock signal is brought out to T2 pin (P1.0).
–
OSC
F
OSC
/2. The timer repeatedly counts to overflow from a loaded value.
=
--------------------------------------------------------------------------------------
4
(UP COUNTING RELOAD VALUE)
(:6 in X2 mode)
(DOWN COUNTING RELOAD VALUE)
65536 RCAP2H
T2
:
12
RCAP2L
(8-bit)
(8-bit)
(8-bit)
TL2
FFh
–
F
T2CONreg
osc
RCAP2H
C/T2
(8-bit)
(8-bit)
TH2
(8-bit)
0
FFh
1
TS83C51RB2/RC2/RD2
TS87C51RB2/RC2/RD2
RCAP2L
T2CONreg
TR2
TS80C51RA2/RD2
T2EX:
if DCEN=1, 1=UP
if DCEN=1, 0=DOWN
if DCEN = 0, up counting
T2CONreg
TOGGLE
TF2
T2CONreg
EXF2
INTERRUPT
TIMER 2
19