EM78P257
OTP ROM
4.11 MOUSE APPLICATION MODE
1. Overview & Features
Overview:
Fig.25 shows how EM78P257A/B communicates with PS/2 connector of PC.
Features:
• RC oscillation.
• Six photo-couples input.
MOUSEN
VCC
+
X1(TCC1)
C1
MOUSEN
4.5R
-
After MCU process
send data to PC
R
15K
TCCA(UP/DOWN Counter)
MOUSEN
X2(TCC2)
VCC
+
C2
4.5R
-
R
15K
MOUSEN
VCC
+
Y1(TCC3)
C3
4.5R
MOUSEN
-
After MCU process
send data to PC
R
15K
TCCB(UP/DOWN Counter)
MOUSEN
Y2(TCC4)
VCC
+
C4
-
4.5R
R
15K
This specification is subject to change without prior notice.
53
07.27.2004 (V1.4)