SN8P2200 Series
USB 1.1 Low-Speed 8-Bit Micro-Controller
SONiX TECHNOLOGY CO., LTD
Page 108
Version 1.7
10.3
PS2_1 DESCRIPITON
PS2_1 interface is from SCK and SDA pins which open-drain structure. SCKM, SDAM bits control SCK, SDA direction.
PS2_1 builds in internal 5K ohm pull-up resistors controlled by PS2ENB bit of PS2M register. PS2ENB=0, internal
pull-up resistors disable and SCK, SDA are open-drain without pull-up resistor. PS2ENB=1, internal pull-up resistor
enable. PS/2 communication is controlled by firmware.
PS2ENB
VDD (5V)
SCKM
5K
ohm
Output
Latch
SCK
SCK
HOST Terminal
PS2ENB
VDD (5V)
SDAM
5K
ohm
Output
Latch
SDA
SDA
PS2M initial value = 0xxx 0000
0AFH
Bit 7
Bit 6
Bit 5
Bit 4
Bit 3
Bit 2
Bit 1
Bit 0
PS2M
PS2ENB -
-
- SDA SCK SDAM
SCKM
Read/Write
R/W -
-
- R/W R/W R/W R/W
After
reset
0 - - - 0 0 0 0
Bit 7
PS2ENB:
PS2 internal 5K ohm pull-up resistor control bit.
0 = Disable.
1 = Enable.
Bit [3:2]
SDA, SCK:
SDA, SCK data buffer.
0 = Data 0.
1 = Data 1.
Bit [1:0]
SDAM, SCKM:
SDA, SCK mode control bit.
0 = Input mode.
1 = Output mode.
Note: Use PS2_1 for PS/2 communication, the USB must be disable (UDE=0).