38B5 Group User’s Manual
1-29
HARDWARE
FUNCTIONAL DESCRIPTION
Fig. 22 Structure of serial I/O1 control registers 1, 2
b7
b0
P62/SRDY1 P64/SBUSY1 pin control bits
0000: Pins P62 and P64 are I/O ports
0001: Not used
0010: P62 pin is an SRDY1 output, P64 pin is an I/O port.
0011: P62 pin is an SRDY1 output, P64 pin is an I/O port.
0100: P62 pin is an I/O port, P64 pin is an SBUSY1 input.
0101: P62 pin is an I/O port, P64 pin is an SBUSY1 input.
0110: P62 pin is an I/O port, P64 pin is an SBUSY1 output.
0111: P62 pin is an I/O port, P64 pin is an SBUSY1 output.
1000: P62 pin is an SRDY1 input, P64 pin is an SBUSY1 output.
1001: P62 pin is an SRDY1 input, P64 pin is an SBUSY1 output.
1010: P62 pin is an SRDY1 input, P64 pin is an SBUSY1 output.
1011: P62 pin is an SRDY1 input, P64 pin is an SBUSY1 output.
1100: P62 pin is an SRDY1 output, P64 pin is an SBUSY1 input.
1101: P62 pin is an SRDY1 output, P64 pin is an SBUSY1 input.
1110: P62 pin is an SRDY1 output, P64 pin is an SBUSY1 input.
1111: P62 pin is an SRDY1 output, P64 pin is an SBUSY1 input.
Serial I/O1 control register 2
(SIO1CON2 (SC12): address 001A 16)
P51/SOUT1 P-channel output disable bit
0: CMOS 3-state (P-channel output is valid.)
1: N-channel open-drain (P-channel output is invalid.)
SOUT1 pin control bit (at no-transfer serial data)
0: Output active
1: Output high-impedance
SBUSY1 output SSTB1 output function selection bit
(Valid in automatic transfer mode)
0: Functions as each 1-byte signal
1: Functions as signal for all transfer data
Serial transfer status flag
0: Serial transfer completion
1: Serial transferring
b7
b0
Serial I/O1 control register 1
(SIO1CON1 (SC11):address 001916)
Serial I/O1 synchronous clock selection bits (P6 5/SSTB1 pin control bit)
00: Internal synchronous clock (P6 5 pin is an I/O port.)
01: External synchronous clock (P6 5 pin is an I/O port.)
10: Internal synchronous clock (P6 5 pin is an SSTB1 output.)
11: Internal synchronous clock (P6 5 pin is an SSTB1 output.)
Transfer mode selection bit
0: Full duplex (transmit and receive) mode (P5 0 pin is an SIN1 input.)
1: Transmit-only mode (P50 pin is an I/O port.)
Serial I/O initialization bit
0: Serial I/O initialization
1: Serial I/O enabled
Serial I/O1 clock pin selection bit
0:SCLK11 (P53/SCLK12 pin is an I/O port.)
1:SCLK12 (P52/SCLK11 pin is an I/O port.)
Transfer direction selection bit
0: LSB first
1: MSB first
Serial transfer selection bits
00: Serial I/O disabled (pins P62,P64,P65,and P50—P53 are I/O ports)
01: 8-bit serial I/O
10: Not available
11: Automatic transfer serial I/O (8-bits)