18 UART
S1C17704 TECHNICAL MANUAL
EPSON
18-19
0x4104: UART Control Register (UART_CTL)
Register name Address
Bit
Name
Function
Setting
Init. R/W
Remarks
UART Control
Register
(UART_CTL)
0x4104
(8 bits)
D7
–
reserved
–
–
–
0 when being read.
D6
REIEN
Receive error int. enable
1 Enable
0 Disable
0
R/W
D5
RIEN
Receive buffer full int. enable
1 Enable
0 Disable
0
R/W
D4
TIEN
Transmit buffer empty int. enable
1 Enable
0 Disable
0
R/W
D3–2
–
reserved
–
–
–
0 when being read.
D1
RBFI
Receive buffer full int. condition
1 2 bytes
0 1 byte
0
R/W
D0
RXEN
UART enable
1 Enable
0 Disable
0
R/W
D7 Reserved
D6
REIEN: Receive Error Interrupt Enable Bit
Enables an interrupt request to be output to the ITC when a receive error has occurred.
1
(R/W):
Enable
0 (R/W): Disable (default)
Set this bit to 1 when processing receive errors in the interrupt handler routine.
D5
RIEN: Receive Buffer Full Interrupt Enable Bit
Enables an interrupt request to be output to the ITC when the receive data buffer receives the number of
data specified by RBFI (D1).
1
(R/W):
Enable
0 (R/W): Disable (default)
Set this bit to 1 when reading the received data in the interrupt handler routine.
D4
TIEN: Transmit Buffer Empty Interrupt Enable Bit
Enables an interrupt request to be output to the ITC when the transmit data written to the transmit data
buffer is transferred to the shift register (when data transmission starts).
1
(R/W):
Enable
0 (R/W): Disable (default)
Set this bit to 1 when writing transmit data to the transmit data buffer in the interrupt handler routine.
D[3:2] Reserved
D1
RBFI: Receive Buffer Full Interrupt Condition Setup Bit
Sets the number of data in the receive data buffer to generate a receive-buffer full interrupt.
1 (R/W): 2 bytes
0 (R/W): 1 byte (default)
When the specified number of received data is loaded to the receive data buffer, the UART outputs an
interrupt request pulse to the ITC if the receive buffer full interrupt has been enabled (RIEN = 1). If
RBFI is 0, an interrupt request pulse is output when a received data is loaded to the receive data buffer
(when the RDRY flag (D1/UART_ST register) goes 1). If RBFI is 1, an interrupt request pulse is output
when two received data occupy the receive data buffer (when the RD2B flag (D3/UART_ST register)
goes 1).
D0
RXEN: UART Enable Bit
Enables the UART to transmit/receive data.
1
(R/W):
Enable
0 (R/W): Disable (default)
Before the UART can transmit/receive data, RXEN must be set to 1. When RXEN is set to 0, data
transmission/reception is disabled. Always make sure RXEN = 0 before setting the transfer conditions.
Writing 0 to RXEN also clears the transmit/receive data buffers.
Summary of Contents for S1C17704
Page 1: ...TECHNICAL MANUAL S1C17704 CMOS 16 BIT SINGLE CHIP MICROCOMPUTER ...
Page 22: ...1 OVERVIEW 1 10 EPSON S1C17704 TECHNICAL MANUAL THIS PAGE IS BLANK ...
Page 42: ...3 MEMORY MAP BUS CONTROL 3 12 EPSON S1C17704 TECHNICAL MANUAL THIS PAGE IS BLANK ...
Page 82: ...6 INTERRUPT CONTROLLER ITC 6 26 EPSON S1C17704 TECHNICAL MANUAL THIS PAGE IS BLANK ...
Page 108: ...8 CLOCK GENERATOR CLG 8 8 EPSON S1C17704 TECHNICAL MANUAL THIS PAGE IS BLANK ...
Page 112: ...9 PRESCALER PSC 9 4 EPSON S1C17704 TECHNICAL MANUAL THIS PAGE IS BLANK ...
Page 138: ...10 I O PORTS P 10 26 EPSON S1C17704 TECHNICAL MANUAL THIS PAGE IS BLANK ...
Page 156: ...11 16 BIT TIMERS T16 11 18 EPSON S1C17704 TECHNICAL MANUAL THIS PAGE IS BLANK ...
Page 208: ...14 8 BIT OSC1 TIMER T8OSC1 14 16 EPSON S1C17704 TECHNICAL MANUAL THIS PAGE IS BLANK ...
Page 234: ...16 STOPWATCH TIMER SWT 16 14 EPSON S1C17704 TECHNICAL MANUAL THIS PAGE IS BLANK ...
Page 242: ...17 WATCHDOG TIMER WDT 17 8 EPSON S1C17704 TECHNICAL MANUAL THIS PAGE IS BLANK ...
Page 264: ...18 UART 18 22 EPSON S1C17704 TECHNICAL MANUAL THIS PAGE IS BLANK ...
Page 300: ...20 I2C 20 20 EPSON S1C17704 TECHNICAL MANUAL THIS PAGE IS BLANK ...
Page 320: ...21 REMOTE CONTROLLER REMC 21 20 EPSON S1C17704 TECHNICAL MANUAL THIS PAGE IS BLANK ...
Page 360: ...24 ON CHIP DEBUGGER DBG 24 6 EPSON S1C17704 TECHNICAL MANUAL THIS PAGE IS BLANK ...
Page 362: ...25 BASIC EXTERNAL WIRING DIAGRAM 25 2 EPSON S1C17704 TECHNICAL MANUAL THIS PAGE IS BLANK ...