M30622MA-XXXFP RENESAS [Renesas Technology Corp], M30622MA-XXXFP Datasheet - Page 393

• Manufacturer Part Number: M30622MA-XXXFP
• Description: 16-BIT SINGLE-CHIP MICROCOMPUTER M16C FAMILY
• Manufacturer: RENESAS [Renesas Technology Corp]

SI/O3, 4
378
2.6 SI/O3, 4
Figure 2.6.1. Memory map of serial I/O3, 4-related registers
2.6.1 Overview
SI/O3, 4 carries out 8-bit data communications in synchronization with the clock. The following is an
overview of the SI/O3, 4.
(1) Transmission/reception format
(2) Transfer rate
(3) Function selection
(6) Input to the serial I/O and the direction register
(7) Pins related to the SI/O3, 4
(8) Registers related to the SI/O3, 4
8-bit data
If the internal clock is selected as the transfer clock, the divide-by-2 frequency, resulting from the bit
rate generator division, becomes the transfer rate. The bit rate generator count source can be se-
lected from the following: f
clock by 1, 8, and 32 respectively.
Furthermore, if an external clock is selected as the transfer clock, the clock frequency input to the CLK
pin becomes the transfer rate.
For SI/O3, 4, the following functions can be selected:
(a) Function for choosing which bit to transmit first
(b) Choosing output level when not transferring
To input an external signal to the serial I/O, set the direction register of the relevant port to input.
• CLK3, CLK4 pins
• S
• S
Figure 2.6.1 shows the memory map of SI/O3, 4-related registers, and Figures 2.6.2 show SI/O3, 4-
related registers.
This function is to choose whether to transmit data from bit 0 or from bit 7. Choose either of the
following:
• LSB first
• MSB first
• Internal clock
• External clock
IN3
OUT3
, S
, S
IN4
OUT4
pins
0048
0049
0360
0361
0362
0363
0364
0365
0366
0367
Data is transmitted from bit 0.
Data is transmitted from bit 7.
pins Output pins for data
16
16
16
16
16
16
16
16
16
16
SI/O3 transmit/receive control register (S3C)
SI/O4 transmit/receive register (S4TRR)
SI/O4 interrupt control register (S4IC)
SI/O3 interrupt control register (S3IC)
SI/O3 transmit/receive register (S3TRR)
SI/O4 control register (S4C)
SI/O3
SI/O4
High-impedance output.
"H" or "L" output level is selected.
Input/output pins for the transfer clock
Input pins for data
1
, f
bit rate generator (S3BRG)
bit rate generator (S4BRG)
8
, and f
32
. Clocks f
1
, f
8
, and f
32
are derived by dividing the CPU’s main
SINGLE-CHIP 16-BIT CMOS MICROCOMPUTER
Mitsubishi microcomputers
M16C / 62 Group