m38039mf-xxxsp Mitsumi Electronics, Corp., m38039mf-xxxsp Datasheet - Page 56

• Manufacturer Part Number: m38039mf-xxxsp
• Description: Single-chip 8-bit Cmos Microcomputer
• Manufacturer: Mitsumi Electronics, Corp.

Serial I/O2
The serial I/O2 function can be used only for clock synchronous
serial I/O.
For clock synchronous serial I/O2, the transmitter and the receiver
must use the same clock. If the internal clock is used, transfer is
started by a write signal to the serial I/O2 register.
[Serial I/O2 Control Register (SIO2CON)]
001D
The serial I/O2 control register contains eight bits which control
various serial I/O2 functions.
Fig. 46 Block diagram of serial I/O2
56
P 5
P 5
P 5
(f(X
P 5
16
3
1
2
/ S
/ S
/ S
CIN
0
f ( X
/ S
R D Y 2
O U T 2
C L K 2
) in low-speed mode)
I N 2
I N
)
S e r i a l I / O 2 p o r t s e l e c t i o n b i t
S e r i a l I / O 2 p o r t s e l e c t i o n b i t
S
R D Y 2
P 5
“ 1 ”
“ 0 ”
“ 0 ”
P5
“ 1 ”
P 5
o u t p u t e n a b l e b i t
“ 1 ”
“ 0 ”
2
1
l a t c h
3
latch
l a t c h
S
R D Y 2
Serial I/O2 synchronous
S y n c h r o n i z a t i o n
c i r c u i t
clock selection bit
External clock
“1”
“ 0 ”
Serial I/O counter 2 (3)
Serial I/O shift register 2 (8)
Fig. 45 Structure of serial I/O2 control register
b 7
1/8
1/16
1/32
1/64
1/128
1/256
SINGLE-CHIP 8-BIT CMOS MICROCOMPUTER
b 0
Serial I/O2 control register
(SIO2CON : address 001D
x x x x
x
x
I n t e r n a l s y n c h r o n o u s
c l o c k s e l e c t i o n b i t s
Internal synchronous clock selection bits
Serial I/O2 port selection bit
S
Transfer direction selection bit
Serial I/O2 synchronous clock selection bit
P5
RDY2
b 2 b 1 b 0
0 0 0: f(X
0 0 1: f(X
0 1 0: f(X
0 1 1: f(X
1 1 0: f(X
1 1 1: f(X
0: CMOS output (in output mode)
1: N-channel open drain output (in output mode)
0: I/O port
1: S
0: I/O port
1: S
0: LSB first
1: MSB first
0: External clock
1: Internal clock
MITSUBISHI MICROCOMPUTERS
1
/S
x
OUT2
OUT2
RDY2
output enable bit
,S
IN
IN
IN
IN
IN
IN
P-channel output disable bit
signal output
3803/3804 Group
)/8 (f(X
)/16 (f(X
)/32 (f(X
)/64 (f(X
)/128 (f(X
)/256 (f(X
CLK2
signal output
CIN
Data bus
CIN
CIN
CIN
CIN
CIN
)/8 in low-speed mode)
)/16 in low-speed mode)
)/32 in low-speed mode)
)/64 in low-speed mode)
16
)/128 in low-speed mode)
)/256 in low-speed mode)
)
Serial I/O2
interrupt request