EM78P221/2N
8-Bit Microcontroller with OTP ROM
Product Specification (V1.0) 10.19.2007
•
11
(This specification is subject to change without further notice)
6.2.7 R4 (Select Indirect Address)
Bits 7~6:
not used, fixed to 0 all the time.
Bit 5 ~ Bit 0:
used to select registers (Address
:
00 ~ 3F) in indirect addressing mode.
6.2.8 Bank 0-R5 (Port 5)
Bit 7
Bit 6
Bit 5
Bit 4
Bit 3
Bit 2
Bit 1
Bit 0
P57 P56 P55 P54 P53 P52 P51 P50
Bits 7 ~ 0 (P57 ~ P50):
I/O data bits
6.2.9
Bank 0-R6 (Port 6)
Bit 7
Bit 6
Bit 5
Bit 4
Bit 3
Bit 2
Bit 1
Bit 0
P67 P66 P65 P64 P63 P62 P61 P60
Bits 7 ~ 0 (P67 ~ P60):
I/O data bits
6.2.10 Bank 0-R7 (Port 7)
Bit 7
Bit 6
Bit 5
Bit 4
Bit 3
Bit 2
Bit 1
Bit 0
P77 P76 P75 P74 P73 P72 P71 P70
Bits 7 ~ 0 (P77 ~ P70):
I/O data bits
[With Simulator]:
P73 ~ P72 are input or open-drain output pins.
[With EM78P221/2N]:
P73 ~ P72 are general input or output pins.
6.2.11 Bank 0-R8 (Port 8)
Bit 7
Bit 6
Bit 5
Bit 4
Bit 3
Bit 2
Bit 1
Bit 0
0
0 NREN 0
0
0 P81 P80
Bits 7~6, 4~2, 0:
not used, fixed to 0 all the time.
Bit 5 (NREN):
Noise rejection enable
0
= disable noise rejection (Default)
1
= enable noise rejection. However in crystal oscillator mode
(LXT2), the noise rejection circuit is always disabled.
Bits 1 ~0 (P81~P80):
I/O data bit.
6.2.12 Bank 0-R9~RD (Reserve)
Bits 7~0:
not used, fixed to "0" all the time.