AN2131QC Cypress Semiconductor Corp, AN2131QC Datasheet - Page 308

• Manufacturer Part Number: AN2131QC
• Description: IC MCU 8051 8K RAM 24MHZ 80BQFP
• Manufacturer: Cypress Semiconductor Corp
• Series: EZ-USB®r

Specifications of AN2131QC

• Applications: USB Microcontroller
• Core Processor: 8051
• Program Memory Type: ROMless
• Controller Series: AN213x
• Ram Size: 8K x 8
• Interface: I²C, USB
• Number Of I /o: 24
• Voltage - Supply: 3 V ~ 3.6 V
• Operating Temperature: 0°C ~ 70°C
• Mounting Type: Surface Mount
• Package / Case: 80-QFP
• Lead Free Status / RoHS Status: Contains lead / RoHS non-compliant
• Other names: 428-1307

C.2.8.4
When CP/RL2 = 0, Timer 2 is configured for the auto-reload mode illustrated in Figure C-5..
Control of counter input is the same as for the other 16-bit counter modes. When the count
increments from FFFFh, Timer 2 sets the TF2 flag and the starting value is reloaded into TL2
and TH2. The software must preload the starting value into the RCAP2L and RCAP2H
registers.
When Timer 2 is in auto-reload mode, a reload can be forced by a high-to-low transition on
the T2EX pin, if enabled by EXEN2 = 1.
C.2.8.5
Setting either RCLK or TCLK to 1 configures Timer 2 to generate baud rates for Serial Port 0
in serial mode 1 or 3. In baud rate generator mode, Timer 2 functions in auto-reload mode.
However, instead of setting the TF2 flag, the counter overflow is used to generate a shift clock
for the serial port function. As in normal auto-reload mode, the overflow also causes the
preloaded start value in the RCAP2L and RCAP2H registers to be reloaded into the TL2 and
TH2 registers.
When either TCLK = 1 or RCLK = 1, Timer 2 is forced into auto-reload operation, regardless
of the state of the CP/RL2 bit.
When operating as a baud rate generator, Timer 2 does not set the TF2 bit. In this mode, a
Timer 2 interrupt can only be generated by a high-to-low transition on the T2EX pin setting
the EXF2 bit, and only if enabled by EXEN2 = 1.
C - 12
CLK24
T2 pin
T2EX pin
16-Bit Timer/Counter Mode with Auto-Reload
Baud Rate Generator Mode
EXEN2
TR2
Divide by 12
Divide by 4
Figure C-5. Timer 2 - Timer/Counter with Auto Reload
Appendix C: 8051 Hardware Description
1
0
T2M
0
1
C/ T2
CLK
0
0
EXF2
RCAP2L
TL2
7
7
8
8
RCAP2H
TH2
TF2
EZ-USB TRM v1.9
15
15
INT