AN2135SC Cypress Semiconductor Corp, AN2135SC Datasheet - Page 309

• Manufacturer Part Number: AN2135SC
• Description: IC MCU 8051 8K RAM 24MHZ 44QFP
• Manufacturer: Cypress Semiconductor Corp
• Series: EZ-USB®r

Specifications of AN2135SC

• 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: 8
• Voltage - Supply: 3 V ~ 3.6 V
• Operating Temperature: 0°C ~ 70°C
• Mounting Type: Surface Mount
• Package / Case: 44-QFP
• Lead Free Status / RoHS Status: Contains lead / RoHS non-compliant
• Other names: 428-1308

The counter time base in baud rate generator mode is CLK24/2. To use an external clock
source, set C/T2 to 1 and apply the desired clock source to the T2 pin.
C.3
The 8051 core provides two serial ports. Serial Port 0 is identical in operation to the standard
8051 serial port. Serial Port 1 is identical to Serial Port 0, except that Timer 2 cannot be used
as the baud rate generator for Serial Port 1.
Each serial port can operate in synchronous or asynchronous mode. In synchronous mode,
8051 generates the serial clock and the serial port operates in half-duplex mode. In
asynchronous mode, the serial port operates in full-duplex mode. In all modes, 8051 buffers
received data in a holding register, enabling the UART to receive an incoming byte before the
software has read the previous value.
Each serial port can operate in one of four modes, as outlined in Table C-7..
EZ-USB TRM v1.9
T2EX pin
T2 pin
CLK24
EXEN2
TR2
Serial Interface
Divide
by 2
1
0
Figure C-6. Timer 2 - Baud Rate Generator Mode
C/ T2
Appendix C: 8051 Hardware Description
EXF2
0
0
CLK
TL2
RCAP2L
TIMER 2 INTERRUPT
7
7
8
8
RCAP2H
TH2
15
15
Divide
TIMER 1 OVERFLOW
1
1
by 2
RCLK
TCLK
0
0
0
1
Divide
by 16
Divide
by 16
CLOCK
SMOD1
CLOCK
RX
TX
C - 13