Renesas M16C Laptop User Manual


 
Rev.1.10 Jul 01, 2005 page 136 of 318
REJ09B0124-0110
M16C/6N Group (M16C/6NK, M16C/6NM) 14. Serial I/O
Under development
This document is under development and its contents are subject to change.
Figure 14.9 U0SMR2 to U2SMR2 Registers and U0SMR3 to U2SMR3 Registers
b7 b6 b5 b4 b3 b2 b1 b0
Function
UARTi Special Mode Register 2 (i = 0 to 2)
Bit Name
Bit
Symbol
Symbol Address After Reset
U0SMR2 to U2SMR2 01EEh, 01F2h, 01F6h X0000000b
RW
IICM2
CSC
SWC
Clock-Synchronous
Bit
SCL Wait Output Bit
I
2
C Mode Select Bit 2
ALS
SDA Output Stop Bit
See Table 14.12 I
2
C Mode Functions
0 : Disabled
1 : Enabled
0 : Disabled
1 : Enabled
0 : Disabled
1 : Enabled
RW
RW
RW
RW
Nothing is assigned. When write, set to "0".
When read, its content is indeterminate.
-
(b7)
-
SDA Output Disable
Bit
SDHI
0: Enabled
1: Disabled (high-impedance)
RW
SCL Wait Output
Bit 2
SWC2
0: Transfer clock
1: "L" output
RW
UARTi Initialization
Bit
STAC
0 : Disabled
1 : Enabled
RW
b7 b6 b5
NOTES:
1. The DL2 to DL0 bits are used to generate a delay in SDAi output by digital means during I
2
C mode.
In other than I
2
C mode, set these bits to "000b" (no delay).
2. The amount of delay varies with the load on SCLi and SDAi pins. Also, when using an external clock,
the amount of delay increases by about 100 ns.
b7 b6 b5 b4 b3 b2 b1 b0
Function
UARTi Special Mode Register 3 (i = 0 to 2)
Bit Name
Bit
Symbol
Symbol Address After Reset
U0SMR3 to U2SMR3 01EDh, 01F1h, 01F5h 000X0X0Xb
RW
-
(b0)
CKPH
-
(b2)
Clock Phase Set Bit
Nothing is assigned. When write, set to "0".
When read, its content is indeterminate.
-
(b4)
Nothing is assigned. When write, set to "0".
When read, its content is indeterminate.
Nothing is assigned When write, set to "0".
When read, its content is indeterminate.
NODC
Clock Output Select
Bit
0 : Without clock delay
1 : With clock delay
0 : CLKi is CMOS output
1 : CLKi is N channel open-drain output
RW
-
-
RW
DL2
DL1 RW
RW
SDAi Digital Delay
Setup Bit
(1) (2)
DL0
0 0 0 : Without delay
0 0 1 :
1 to 2 cycle(s) of UiBRG count source
0 1 0 :
2 to 3 cycles of UiBRG count source
0 1 1 :
3 to 4 cycles of UiBRG count source
1 0 0 :
4 to 5 cycles of UiBRG count source
1 0 1 :
5 to 6 cycles of UiBRG count source
1 1 0 :
6 to 7 cycles of UiBRG count source
1 1 1 :
7 to 8 cycles of UiBRG count source
RW
-