gc80c520a CORERIVER Semiconductor, gc80c520a Datasheet - Page 52

• Manufacturer Part Number: gc80c520a
• Description: Midas1.0 Family Mask Rom/eprom/romless 8-bit Turbo Microcontrollers
• Manufacturer: CORERIVER Semiconductor

6.2.5.4 Mode 3
This mode is the same as Mode 2, except that the baud rate is programmable. Mode 3 may have a
variable baud rate generated from either Timer 1 or 2 depending on the state of TCLK and RCLK. Timer 1
should also be initialized if Mode 1 and 3 are used. In all four modes, transmission is started by any
instruction that uses SBUF as a destination register. Reception is initiated in Mode 0 when RI=0 and
REN=1. This will shift in 8 bits on the RxD pin. Reception is initiated in the other modes by the incoming
start bit if REN=1. The external device will start the communication by transmitting the start bit.
Write to SBUF
Sample Times
Stop bit Gen.
[Transmit]
[Receive]
Bit Detector
RX CLOCK
TX Clock
SEND
Data
Shift
Shift
RXD
TXD
RI
TI
S1
/16 Reset
Start bit
Start bit
Figure 6-23 UART Mode 2 Timing
D0
D0
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D1
D1
D2
D2
D3
D3
D4
D4
D5
D5
Functional Description
D6
D6
D7
D7
TB8
RB8
Stop bit
Stop bit