P89V662FBC,557 NXP Semiconductors, P89V662FBC,557 Datasheet - Page 45

• Manufacturer Part Number: P89V662FBC,557
• Description: IC 80C51 MCU FLASH 32K 44-TQFP
• Manufacturer: NXP Semiconductors
• Series: 89Vr

Specifications of P89V662FBC,557

• Program Memory Type: FLASH
• Program Memory Size: 32KB (32K x 8)
• Package / Case: 44-TQFP
• Core Processor: 8051
• Core Size: 8-Bit
• Speed: 40MHz
• Connectivity: I²C, SPI, UART/USART
• Peripherals: POR, PWM, WDT
• Number Of I /o: 36
• Ram Size: 1K x 8
• Voltage - Supply (vcc/vdd): 4.5 V ~ 5.5 V
• Oscillator Type: Internal
• Operating Temperature: -40°C ~ 85°C
• Processor Series: P89V6x
• Core: 80C51
• Data Bus Width: 8 bit
• Data Ram Size: 1 KB
• Interface Type: I2C/UART
• Maximum Clock Frequency: 40 MHz
• Number Of Programmable I/os: 36
• Number Of Timers: 3
• Operating Supply Voltage: 4.5 V to 5.5 V
• Maximum Operating Temperature: + 85 C
• Mounting Style: SMD/SMT
• 3rd Party Development Tools: PK51, CA51, A51, ULINK2
• Minimum Operating Temperature: - 40 C
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• For Use With: 622-1001 - USB IN-CIRCUIT PROG 80C51ISP
• Eeprom Size: -
• Data Converters: -
• Lead Free Status / Rohs Status: Lead free / RoHS Compliant
• Other names: 568-2435; 935280832557; P89V662FBC

NXP Semiconductors
P89V660_662_664_3
Product data sheet
Fig 19. Timer 2 in Auto-reload mode (DCEN = 0)
OSC
T2 pin
6.6.2 Auto-reload mode (up or down-counter)
T2EX pin
In the 16-bit auto-reload mode, Timer 2 can be configured as either a timer or counter (via
C/T2 in T2CON), then programmed to count up or down. The counting direction is
determined by bit DCEN (Down-counter Enable) which is located in the T2MOD register
(see
counting up. If the DCEN bit is set, Timer 2 can count up or down depending on the value
of the T2EX pin.
Figure 19
6
In this mode, there are two options selected by bit EXEN2 in T2CON register. If
EXEN2 = 0, then Timer 2 counts up to 0FFFFH and sets the TF2 (Overflow Flag) bit upon
overflow. This causes the Timer 2 registers to be reloaded with the 16-bit value in
RCAP2L and RCAP2H. The values in RCAP2L and RCAP2H are preset by software
means.
Auto reload frequency when Timer 2 is counting up can be determined from this formula:
Where SupplyFrequency is either f
(C/T2 = 1).
If EXEN2 = 1, a 16-bit reload can be triggered either by an overflow or by a 1-to-0
transition at input T2EX. This transition also sets the EXF2 bit. The Timer 2 interrupt, if
enabled, can be generated when either TF2 or EXF2 is ‘1’.
Microcontroller’s hardware will need three consecutive machine cycles in order to
recognize falling edge on T2EX and set EXF2 = 1: in the first machine cycle pin T2EX has
to be sampled as ‘1’; in the second machine cycle it has to be sampled as ‘0’, and in the
third machine cycle EXF2 will be set to ‘1’.
------------------------------------------------------------------------------- -
65536
transition
detector
Table 34
SupplyFrequency
C/T2 = 0
C/T2 = 1
RCAP2H RCAP2L
shows Timer 2 counting up automatically (DCEN = 0).
and
EXEN2
Table
control
Rev. 03 — 10 November 2008
TR2
35). When reset is applied, DCEN = 0 and Timer 2 will default to
control
reload
osc
RCAP2L RCAP2H
80C51 with 512 B/1 kB/2 kB RAM, dual I
(8-bits)
TL2
(C/T2 = 0) or frequency of signal on T2 pin
(8-bits)
TH2
P89V660/662/664
EXF2
TF2
© NXP B.V. 2008. All rights reserved.
002aaa524
interrupt
timer 2
2
C-bus, SPI
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