11
17. Hardware Description
17.1. Microcomputer
The H8/3687 Series Microcomputer was chosen for the following reasons:
* Cheaper.
* High-speed CPU with sixteen 16-bit registers.
* 33 interrupt sources and efficient interrupt processing.
* Four versatile timers.
* Two on-chip serial communication interface channels.
* 8-channel 10-bit resolution A/D converter.
*I
2
C bus interface.
* Less chip count.
* Pin compatibility of similar package with difference ROM sizes.
* Instruction set is compatible with the H8/300 CPU.
* Good support.
17.2. Pin Assignment
Pin
I/O
Assignment
Device
Remark
P10/TMOW I
-
P11/PWM I
-
P12 I
ACIN
AC
Power Detects
AC
Power
P14/IRQ0 I
-
P15/IRQ1/TMIB1 I
-
P16/IRQ2 I
-
P17/IRQ3/TRGV I K0
Keyboard
Key
Return
Line
P20/SCK3 O
RTS MAX232
RS-232C
P21/RXD I
RXD
MAX232
RS-232C
P22/TXD O
TXD MAX232
RS-232C
P23 I
CTS
MAX232 RS-232C
P24
O
CVD
R12
Device Power Control
P30 O
T1
KEYBOARD
Key
Scanning
Line
P31 O
T2
KEYBOARD
Key
Scanning
Line
P32 O
T3
KEYBOARD
Key
Scanning
Line
P33 O
T4
KEYBOARD
Key
Scanning
Line
P34 O
T5
KEYBOARD
Key
Scanning
Line
P35 O
T6
KEYBOARD
Key
Scanning
Line
P36 I
-
P37 I
-
P50/WKP0 I
-
P51/ WKP 1
I
-
P52/ WKP 2
O
TBT
R8
Controls BATT Detector
P53/ WKP 3
O
CVAD
R6
Controls BATT Power To A/D
P54 WKP 4
O
BTPW
R4
Controls BATT Power To M/B
P55/ WKP 5/ADTRG
O
BTCHG
R2
Controls BATT Charger
P56/SDA I/O
SDA
AT24C128,HMS093AL
EEPROM,LCM
P57/SCL O
SCL
AT24C128,HMS093AL
EEPROM,LCM
P60/FTIOA0
O
RTCCS
3511A
Real Time Clock
P61/FTIOB0
O
RTCSCK
3511A
Real Time Clock
P62/FTOC0
I/O
RTCSIO
3511A
Real Time Clock
P63/FTIOD0 O
CBUZZ
R40
Buzzer
Sounder
P64/FTIOA1
O
ADCHAN
A/D Board
Controls A/D Channel
P65/FTIOB1 O
ADSCLK A/D
Board
Controls A/D Conversion
P66/FTIOC1
O
ADSDI
A/D Board
Controls A/D Conversion
P67/FTIOD1 I
ADSDO A/D
Board
Controls A/D Conversion
P70/SCK3_2 I
-
P71/RXD_2 I
-
P71/TXD_2 I
-
P74/TMRIV O
EEPWP AT24C128
EEPROM
P75/TMCIV I
-
P76/TMOV I
-
