EM78815
8-Bit Microcontroller
Bit 6 (INT6) : External INT6 pin interrupt flag
If Port 76 has a falling edge trigger signal, the CPU will set this bit.
Bit 7 (INT7) : External INT7 pin interrupt flag
If Port 77 has a falling (or rising and falling) edge trigger signal, the
CPU will set this bit.
Signal
Trigger
Remark
INT0
:
Falling edge
INT6
INT7
Falling/Falling & Rising Edge
Controlled by CONT register
7.2.20.2 Page 1 Data RAM Address 1(H)
Bit 7
Bit 6
Bit 5
Bit 4
Bit 3
RAM1A11 RAM1A10 RAM1A9 RAM1A8
R/W-X R/W-X R/W-X R/W-X
Bit 2
Bit 1
Bit 0
−
×
−
×
−
×
−
×
Bit 0~Bit 3 (RAM1A8 ~ RAM1A11) : Data RAM address (Address 8 to Address 11)
for RAM reading.
Bit 4~Bit 7 Undefined Register. These registers are not certain whether 0 or 1.
Do not use these registers.
7.2.20.3 Page 2 CAS Detected Flag, Keyscan
Bit 7
Bit 6
Bit 5
Key strobe Keyscan
R/W-0 R/W-0
Bit 4
Bit 3
Bit 2
Bit 1
Bit 0
CAS
R
LCD1
LCD0
−
×
−
×
−
×
R/W-0
R/W-0
Bit 0~Bit 1 : Undefined register. These bits are unimplemented, not for use.
Bit 2~Bit 3 (LCD0~LCD1) : These two bits are used to enable/disable key scan and
the LCD controller.
LCD1
LCD0
Sates
Keyscan disable (ignore Keyscan bit)
External LCD controller disable
0
0
Keyscan disable (ignore Keyscan bit)
External LCD controller disable
Keyscan disable (ignore Keyscan bit)
External LCD controller disable
Keyscan enable (Keyscan bit must = 1)
External LCD controller enable
0
1
1
1
0
1
Bit 4 (Keyscan) : Key scan function enable control bit.
0/1 → disable/enable
If Keyscan function is enabled (LCD0, LCD1 and Keyscan =1), Port 8
and Port 9 will be pulled high automatically and become key strobe
pins.
Product Specification (V2.4) 08.01.2004
(This specification is subject to change without further notice)
43
ELAN [ ELAN MICROELECTRONICS CORP ]
