AN2131QC Cypress Semiconductor Corp, AN2131QC Datasheet - Page 310

• 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

The SFRs associated with the serial ports are:
C.3.1 803x/805x Compatibility
The implementation of the serial interface is similar to that of the Intel 8052.
C.3.2 Mode 0
Serial mode 0 provides synchronous, half-duplex serial communication. For Serial Port 0,
serial data output occurs on the RXD0OUT pin, serial data is received on the RXD0 pin, and
the TXD0 pin provides the shift clock for both transmit and receive. For Serial Port 1, the
corresponding pins are RXD1OUT, RXD1, and TXD1.
The serial mode 0 baud rate is either CLK24/12 or CLK24/4, depending on the state of the
SM2_0 bit (or SM2_1 for Serial Port 1). When SM2_0 = 0, the baud rate is CLK24/12, when
SM2_0 = 1, the baud rate is CLK24/4.
Mode 0 operation is identical to the standard 8051. Data transmission begins when an
instruction writes to the SBUF0 (or SBUF1) SFR. The UART shifts the data, LSB first, at the
selected baud rate, until the 8-bit value has been shifted out.
Mode 0 data reception begins when the REN_0 (or REN_1) bit is set and the RI_0 (or RI_1)
bit is cleared in the corresponding SCON SFR. The shift clock is activated and the UART
shifts data in on each rising edge of the shift clock until 8 bits have been received. One
C - 14
•
•
•
•
SCON0 - SFR 98h - Serial Port 0 control (Table C-8.).
SBUF0 - SFR 99h - Serial Port 0 buffer.
SCON1 - SFR C0h - Serial Port 1 control (Table C-9.).
SBUF1 - SFR C1h - Serial Port 1 buffer.
(1)
Mode
Timer 2 available for Serial Port 0 only.
0
1
2
3
Async
Async
Async
Async
Sync/
Sync
Appendix C: 8051 Hardware Description
CLK24/4 or
CLK24/12
Timer 1 or Timer 2
CLK24/32 or
CLK24/64
Timer 1 or Timer 2
Table C-7. Serial Port Modes
Baud Clock
1
1
Data
Bits
8
8
9
9
None
1 start, 1 stop
1 start, 1 stop
1 start, 1 stop
Start/Stop
None
None
0, 1, parity
0, 1, parity
Function
9th Bit
EZ-USB TRM v1.9