20 GENERAL-PURPOSE SERIAL INTERFACE (FSIO)
S1C33L26 TECHNICAL MANUAL
Seiko Epson Corporation
20-29
The reload data set in these registers are loaded into the counter, and the counter starts counting down
beginning with the set value, which is used as the initial count. There are two cases in which the re-
load data is loaded into the counter: when the baud-rate timer starts by writing 1 to BRTRUN/FSIO_
BRTRUN
x
register, or when data is automatically reloaded upon counter underflow.
FSIO Ch.
x
Baud-rate Timer Count Data L Registers (FSIO_BRTCDL
x
)
FSIO Ch.
x
Baud-rate Timer Count Data H Registers (FSIO_BRTCDH
x
)
Register name Address
Bit
Name
Function
Setting
Init. R/W
Remarks
FSIO Ch.
x
Baud-rate Timer
Count Data L
Register
(FSIO_
BRTCDL
x
)
0x300708
0x300718
(8 bits)
D7–0 BRTCD[7:0] Baud-rate timer count data [7:0]
0x0 to 0xff
(BRTCD[11:0] = 0x0 to 0xfff)
0x0
R
FSIO Ch.
x
Baud-rate Timer
Count Data H
Register
(FSIO_
BRTCDH
x
)
0x300709
0x300719
(8 bits)
D7–4 –
reserved
–
–
–
0 when being read.
D3–0 BRTCD
[11:8]
Baud-rate timer count data [11:8]
0x0 to 0xf
(BRTCD[11:0] = 0x0 to 0xfff)
0x0
R
D[7:0]/FSIO_BRTCDL
x
, D[3:0]/FSIO_BRTCDH
x
BRTCD
x
[11:0]: Baud-rate Timer Count Data [11:0]
The baud-rate timer data can be read out from these registers. (Default: 0x0)
These registers function as a buffer that retain the counter data when read out, enabling the data to be
read out at any time.
FSIO Ch.
x
Interrupt Flag Registers (FSIO_INTF
x
)
Register name Address
Bit
Name
Function
Setting
Init. R/W
Remarks
FSIO Ch.
x
Interrupt Flag
Register
(FSIO_INTF
x
)
0x30070a
0x30071a
(8 bits)
D7–2 –
reserved
–
–
–
0 when being read.
D1
TDBE_IF
Transmit data buffer empty int. flag 1 Cause of
interrupt
occurred
0 Cause of
interrupt not
occurred
0
R/W Reset by writing 0.
D0
RDBF_IF
Receive data buffer full int. flag
0
R/W
D[7:2]
Reserved
D1
TDBE_IF: Transmit Data Buffer Empty Interrupt Flag Bit
Indicates whether the cause of transmit data buffer empty interrupt has occurred or not.
1 (R):
Cause of interrupt has occurred
0 (R):
No cause of interrupt has occurred (default)
1 (W):
Ignored
0 (W):
Flag is reset
TDBE_IF is set to 1 when the transmit data written to the transmit data buffer is transferred to the shift
register, indicating that the next transmit data can be written to. At the same time a transmit data buffer
empty interrupt request is sent to the ITC if TDBE_IE/FSIO_INTE
x
register is 1. TDBE_IF is reset by
writing 0.
D0
RDBF_IF: Receive Data Buffer Full Interrupt Flag Bit
Indicates whether the cause of receive data buffer full interrupt has occurred or not.
1 (R):
Cause of interrupt has occurred
0 (R):
No cause of interrupt has occurred (default)
1 (W):
Ignored
0 (W):
Flag is reset
RDBF_IF is set to 1 when the number of data specified with FIFOINT[1:0]/FSIO_IRDA
x
register (one
data in standard mode) has been received in the receive data buffer, indicating that received data can be
read. At the same time a receive data buffer full interrupt request is sent to the ITC if RDBF_IE/FSIO_
INTE
x
register is 1. RDBF_IF is reset by writing 0.