Register Descriptions - Hitachi H8/3637 Hardware Manual

Register Configuration: Table 10.3 shows the SCI1 register configuration.
Table 10.3 SCI1 Registers
Name
Serial control register 1
Serial control status register 1
Serial data register U
Serial data register L
10.2.2

Register Descriptions

Serial Control Register 1 (SCR1)
Bit
SNC1
Initial value
Read/Write R/W
SCR1 is an 8-bit read/write register for selecting the operation mode, the transfer clock source,
and the prescaler division ratio.
Upon reset, SCR1 is initialized to H'00. Writing to this register stops a transfer in progress.
Bits 7 and 6—Operation Mode Select 1, 0 (SNC1, SNC0): Bits 7 and 6 select the operation
mode.
Bit 7: SNC1 Bit 6: SNC0
0 0
1
1 0
1
Notes: 1. Pins SI and SO
1
2. Don't set bits SNC1 and SNC0 to 11.
Bits 5 and 4—Reserved Bits: Bits 5 and 4 are reserved: they should always be cleared to 0.
Abbrev.
SCR1
SCSR1
SDRU
SDRL
7 6
SNC0 —
0 0
R/W R/W
Description
8-bit synchronous transfer mode
16-bit synchronous transfer mode
Continuous clock output mode *
Reserved *
should be used as general input or output ports.
1
R/W
R/W
R/W
R/W
R/W
5 4
— CKS3
0 0
R/W R/W
2
Initial Value Address
H'00 H'FFA0
H'9C H'FFA1
Undefined H'FFA2
Undefined H'FFA3
3 2
CKS2 CKS1
0 0
R/W R/W
1
1 0
CKS0
0 0
R/W
(initial value)
213