SN8P1700
8-bit micro-controller build-in 12-bit ADC
10SERIAL INPUT/OUTPUT
TRANSCEIVER (SIO)
OVERVIEW
The SN8P1700provides an 8-bit SIO interface circuit with clock rate selection. The SIOM register can control SIO
operating function, such as: transmit/receive, clock rate, transfer edge and starting this circuit. This SIO circuit will TX
or RX 8-bit data automatically by setting SENB and START bits in SIOM register. The SIOB is an 8-bit buffer, which is
designed to store transfer data. SIOC and SIOR are designed to generate SIO’s clock source with auto-reload function.
The 3-bit I/O counter can monitor the operation of SIO and announce an interrupt request after transmitting/receiving 8
bits data. After transferring 8-bit data, this circuit will be disabled automatically and re-transfer data by programming
SIOM register.
Senb
Data bus
SIOM register
Senb, TxRx
SI/P5.1 pin
Senb
Sckmd
SO/P5.2 pin
SIOB 8-bit buffer
CPUM1,0
Sckmd
SCK/P5.0 pin
CPUM1,0
CPUM1,0
3-bit I/O
counter
SIO Time out
SIOC
8-bit binary counter
reset
Senb
Sedge
Senb
Auto_reload
SIOR register
Srate
Figure 10-1. SIO Interface Circuit Diagram
SONiX TECHNOLOGY CO., LTD
Page 101
Revision 1.94