M37221M4H_15 Datasheet, PDF (101/114 Pages) Renesas Technology Corp – SINGLE-CHIP 8-BIT CMOS MICROCOMPUTER for VOLTAGE SYNTHESIZER with ON-SCREEN DISPLAY CONTROLLER

M37221M4H/M6H/M8H/MAH–XXXSP/FP M37221EASP/FP
Address 00DB16
I²C Clock Control Register
b7 b6 b5 b4 b3 b2 b1 b0
I²C clock control register (S2) [Address 00DB16]
B
Name
Functions
After reset R W
0 SCL frequency control bits _{Setup value of Standard clock High speed}
0
to (CCR0 to CCR4)
CCR4–CCR0 mode clock mode
4
00 to 02 Setup disabled Setup disabled
03
Setup disabled 333
04
Setup disabled 250
05
100 400 (See note)
06
83.3
166
500/CCR value 1000/CCR value
1D
17.2
34.5
1E
16.6
33.3
1F
16.1
32.3
5 SCL mode
specification bit
(FAST MODE)
(at φ = 4 MHz, unit : kHz)
0: Standard clock mode
0
1: High-speed clock mode
6 ACK bit
0: ACK is returned.
0
(ACK BIT)
1: ACK is not returned.
RW
RW
RW
7 ACK clock bit
(ACK)
0: No ACK clock
1: ACK clock
0 _RW
Note: At 400 kHz in the high-speed clock mode, the duty is as below .
“0” period : “1” period = 3 : 2
In the other cases, the duty is as below.
“0” period : “1” period = 1 : 1
Address 00DC16
Serial I/O Mode Register
b7 b6 b5 b4 b3 b2 b1 b0
0
Serial I/O mode register (SM) [Address 00DC16]
B
Name
0, 1 Internal synchronous
clock selection bits
(SM0, SM1)
Functions
b1 b0
0 0: f(XIN)/4
0 1: f(XIN)/16
1 0: f(XIN)/32
1 1: f(XIN)/64
2 Synchronous clock
selection bit (SM2)
3 Serial I/O port
selection bit (SM3)
0: External clock
1: Internal clock
0: P20, P21
1: SCLK, SOUT
4 Fix this bit to “0.”
After reset R W
0 RW
0 RW
0 RW
0 RW
5 Transfer direction
0: LSB first
selection bit (SM5) 1: MSB first
6 ^{Serial input pin}
0: Input signal from SIN pin.
selection bit (SM6) 1: Input signal from SOUT pin.
7 ^{Nothing is assigned. This bit is a write disable bit.}
When this bit is read out, the value is “0.”
0 RW
0 RW
0 R—
Rev.1.00 Oct 01, 2002 page 99 of 110
REJ03B0134-0100Z