
ii
EPSON
S1C88409 TECHNICAL MANUAL
CONTENTS
5.3
Watchdog Timer ........................................................................................... 51
5.3.1 Configuration of watchdog timer .............................................................. 51
5.3.2 Control of watchdog timer ........................................................................ 51
5.3.3 Interrupt function ...................................................................................... 52
5.3.4 I/O memory of watchdog timer ................................................................. 52
5.3.5 Programming notes ................................................................................... 53
5.4
Oscillation Circuit ....................................................................................... 54
5.4.1 Configuration of oscillation circuit .......................................................... 54
5.4.2 Mask option ............................................................................................... 54
5.4.3 OSC1 oscillation circuit ............................................................................ 54
5.4.4 OSC3 oscillation circuit ............................................................................ 55
5.4.5 Switching of CPU clock and operating voltage VD1 ................................ 56
5.4.6 I/O memory of oscillation circuit .............................................................. 58
5.4.7 Programming notes ................................................................................... 59
5.5
Prescaler and Clock Control Circuit for Peripheral Circuits ..................... 60
5.5.1 Configuration of prescaler ........................................................................ 60
5.5.2 Setting of source clock .............................................................................. 60
5.5.3 Prescaler division ratio selection and output control .............................. 61
5.5.4 Control of external clock for event counter .............................................. 62
5.5.5 I/O memory of prescaler ........................................................................... 63
5.5.6 Programming note ..................................................................................... 67
5.6
Input Ports (K ports) .................................................................................... 68
5.6.1 Configuration of input ports ..................................................................... 68
5.6.2 Mask option ............................................................................................... 68
5.6.3 Interrupt function ...................................................................................... 69
5.6.4 I/O memory of input ports ......................................................................... 72
5.6.5 Programming note ..................................................................................... 74
5.7
Output Ports (R ports) ................................................................................. 75
5.7.1 Configuration of output ports ................................................................... 75
5.7.2 High impedance control ............................................................................ 75
5.7.3 DC output .................................................................................................. 75
5.7.4 Special output ............................................................................................ 75
5.7.5 I/O memory of output ports ....................................................................... 76
5.8
I/O Ports (P ports) ....................................................................................... 78
5.8.1 Configuration of I/O ports ........................................................................ 78
5.8.2 Terminal configuration of I/O port and change of function ..................... 78
5.8.3 Mask option ............................................................................................... 80
5.8.4 I/O control registers and I/O mode ........................................................... 80
5.8.5 I/O memory of I/O ports ............................................................................ 81
5.8.6 Programming note ..................................................................................... 82
5.9
Clock Output ................................................................................................ 83
5.9.1 Configuration of clock output control circuit ........................................... 83
5.9.2 Clock output control .................................................................................. 84
5.9.3 I/O memory of clock output ....................................................................... 85
5.9.4 Programming notes ................................................................................... 87
5.10 LCD Controller ............................................................................................ 88
5.10.1 Configuration of LCD controller ............................................................ 88
5.10.2 Output signals ......................................................................................... 89
5.10.3 Display control ........................................................................................ 90
5.10.4 B&W and gray-scale mode setting ......................................................... 90
5.10.5 Display memory ....................................................................................... 91
5.10.6 LCD panel ............................................................................................... 91
5.10.7 Vertical scroll function ............................................................................ 93
5.10.8 Virtual screen function ............................................................................ 93
5.10.9 Data transfer ........................................................................................... 94
5.10.10 Interrupt function .................................................................................. 97