NT6868C Datasheet, PDF (1/15 Pages) List of Unclassifed Manufacturers – Keyboard Controller

NT6868C
Keyboard Controller
Features
n Built-in 6502 8-bit CPU
n 2 MHz CPU operation frequency
n 4K bytes of ROM
n 128 bytes of SRAM
n One 8-bit programmable base timer with 1 - 256 µsec
interval
n 29 programmable bi-directional I/O pins
n 3 LED direct sink pins with internal serial resistors
n Mask optional for built-in RC oscillator with an
external resistor or external ceramic resonator
applied
n Mask optional for DATA/CLK driving capability
n Watch-dog timer
n Built-in power-on reset
n Built-in low voltage reset
n CMOS technology for low power consumption
n Available in 40 pin DIP package and 40 pad CHIP
FORM
General Description
NT6868C is a single chip micro-controller for keyboard
applications. It incorporates a 6502 8-bit CPU core, 4K
bytes of ROM and 128 bytes of RAM used as working
RAM and stack area. It also includes 29 programmable
bi-directional I/O pins and one 8-bit pre-loadable base
timer.
Additionally, it includes a built-in low voltage reset, a
4MHz RC oscillator that only requires an externally
applied or a 4MHz ceramic resonator, and a watch-dog
timer that has a resistor preventing system standstill.
Pin Configuration
GND 1
NC 2
DATA
3
CLK
4
P30
5
P31
6
P32
7
P33
8
P34
9
RESET
10
P00
11
P01
12
P02
13
P03
14
P04
15
P05
16
P06
17
P07
18
P10
19
P11
20
40 OSCI
39 R/OSCO
38
V DD
37 LED2
36
LED1
35 LED0
34 P27
33 P26
32 P25
31
P24
30 P23
29 P22
28 P21
27
P20
26 P17
25 P16
24
P15
23
P14
22
P13
21 P12
Pad Configuration
P PP PP PP PP P
11 11 11 11 00
76 54 32 10 76
26 25 24 23 22 21 20 19 18 17
16
P05
15
P04
P20
27
14
P03
P21
28
13
P02
P22
29
12
P01
P23
30
P24
31
NT6868CH
11
P00
10
RESET
P25
32
9
P34
P26
33
8
P33
P27
34
7
P32
LED0
35
LED1
36
37 38 39 40 1
23 45
6
P31
L VR OG
E
D
/
SN
D
D
O
CD
2
S
I
C
O
N DC P
CAL3
TK 0
A
1
V2.0