SN8P1700
8-bit micro-controller build-in 12-bit ADC
SONiX TECHNOLOGY CO., LTD
Page 147
Revision 1.93
SIOB DATA BUFFER
SIOB initial value = 0000 0000
0B6H
Bit 7
Bit 6
Bit 5
Bit 4
Bit 3
Bit 2
Bit 1
Bit 0
SIOB
X X X X X X X X
R/W R/W R/W R/W R/W R/W R/W R/W
SIOB is the SIO data buffer register. It stores serial I/O transmit and receive data.
SIOR REGISTER DESCRIPTION
SIOR initial value = 0000 0000
0B5H
Bit 7
Bit 6
Bit 5
Bit 4
Bit 3
Bit 2
Bit 1
Bit 0
SIOR
X X X X X X X X
W W W W W W W W
The SIOR is designed for the SIO counter to reload the counted value when end of counting. It is like a post-scaler of
SIO clock source and let SIO has more flexible to setting SCK range. Users can set the SIOR value to setup SIO
transfer time. To setup SIOR value equation to desire transfer time is as following.
SCK frequency = SIO rate / (256 - SIOR)
SIOR = 256 - ( 1 / ( SCK frequency ) * SIO rate )
Example: Setup the SIO clock to be 5KHz. Fosc = 3.58MHz. SIO’s rate = Fcpu = Fosc/4.
SIOR = 256 – (1/(5KHz) * 3.58MHz/4)
= 256 – (0.0002*895000)
= 256 – 179
= 77