C8051F333-GMR Silicon Laboratories Inc, C8051F333-GMR Datasheet - Page 152
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C8051F333-GMR
Manufacturer Part Number
C8051F333-GMR
Description
IC 8051 MCU 4K FLASH 20MLP
Manufacturer
Silicon Laboratories Inc
Series
C8051F33xr
Specifications of C8051F333-GMR
Core Processor
8051
Core Size
8-Bit
Speed
25MHz
Connectivity
SMBus (2-Wire/I²C), SPI, UART/USART
Peripherals
POR, PWM, WDT
Number Of I /o
17
Program Memory Size
4KB (4K x 8)
Program Memory Type
FLASH
Ram Size
768 x 8
Voltage - Supply (vcc/vdd)
2.7 V ~ 3.6 V
Oscillator Type
Internal
Operating Temperature
-40°C ~ 85°C
Package / Case
20-QFN
Processor Series
C8051F3x
Core
8051
Data Bus Width
8 bit
Data Ram Size
768 B
Interface Type
I2C, SPI, UART
Maximum Clock Frequency
25 MHz
Number Of Programmable I/os
17
Number Of Timers
4
Operating Supply Voltage
2.7 V to 3.6 V
Maximum Operating Temperature
+ 85 C
Mounting Style
SMD/SMT
3rd Party Development Tools
KSK-SL-TOOLSTICK, PK51, CA51, A51, ULINK2
Development Tools By Supplier
C8051F330DK
Minimum Operating Temperature
- 40 C
For Use With
336-1451 - ADAPTER PROGRAM TOOLSTICK F330
Lead Free Status / RoHS Status
Lead free / RoHS Compliant
Eeprom Size
-
Data Converters
-
Lead Free Status / Rohs Status
Details
Available stocks
Company
Part Number
Manufacturer
Quantity
Price
Part Number:
C8051F333-GMR
Manufacturer:
SILICON LABS/芯科
Quantity:
20 000
C8051F330/1/2/3/4/5
16.2.2. 9-Bit UART
9-bit UART mode uses a total of eleven bits per data byte: a start bit, 8 data bits (LSB first), a programma-
ble ninth data bit, and a stop bit. The state of the ninth transmit data bit is determined by the value in TB80
(SCON0.3), which is assigned by user software. It can be assigned the value of the parity flag (bit P in reg-
ister PSW) for error detection, or used in multiprocessor communications. On receive, the ninth data bit
goes into RB80 (SCON0.2) and the stop bit is ignored.
Data transmission begins when an instruction writes a data byte to the SBUF0 register. The TI0 Transmit
Interrupt Flag (SCON0.1) is set at the end of the transmission (the beginning of the stop-bit time). Data
reception can begin any time after the REN0 Receive Enable bit (SCON0.4) is set to ‘1’. After the stop bit
is received, the data byte will be loaded into the SBUF0 receive register if the following conditions are met:
(1) RI0 must be logic 0, and (2) if MCE0 is logic 1, the 9th bit must be logic 1 (when MCE0 is logic 0, the
state of the ninth data bit is unimportant). If these conditions are met, the eight bits of data are stored in
SBUF0, the ninth bit is stored in RB80, and the RI0 flag is set to ‘1’. If the above conditions are not met,
SBUF0 and RB80 will not be loaded and the RI0 flag will not be set to ‘1’. A UART0 interrupt will occur if
enabled when either TI0 or RI0 is set to ‘1’.
MARK
START
STOP
D0
D1
D2
D3
D4
D5
D6
D7
D8
BIT
BIT
SPACE
BIT TIMES
BIT SAMPLING
Figure 16.5. 9-Bit UART Timing Diagram
16.3. Multiprocessor Communications
9-Bit UART mode supports multiprocessor communication between a master processor and one or more
slave processors by special use of the ninth data bit. When a master processor wants to transmit to one or
more slaves, it first sends an address byte to select the target(s). An address byte differs from a data byte
in that its ninth bit is logic 1; in a data byte, the ninth bit is always set to logic 0.
Setting the MCE0 bit (SCON0.5) of a slave processor configures its UART such that when a stop bit is
received, the UART will generate an interrupt only if the ninth bit is logic 1 (RB80 = 1) signifying an address
byte has been received. In the UART interrupt handler, software will compare the received address with
the slave's own assigned 8-bit address. If the addresses match, the slave will clear its MCE0 bit to enable
interrupts on the reception of the following data byte(s). Slaves that weren't addressed leave their MCE0
bits set and do not generate interrupts on the reception of the following data bytes, thereby ignoring the
data. Once the entire message is received, the addressed slave resets its MCE0 bit to ignore all transmis-
sions until it receives the next address byte.
Multiple addresses can be assigned to a single slave and/or a single address can be assigned to multiple
slaves, thereby enabling "broadcast" transmissions to more than one slave simultaneously. The master
processor can be configured to receive all transmissions or a protocol can be implemented such that the
master/slave role is temporarily reversed to enable half-duplex transmission between the original master
and slave(s).
156
Rev. 1.7