z08617 ZiLOG Semiconductor, z08617 Datasheet - Page 8

• Manufacturer Part Number: z08617
• Description: Nmos Z8 8-bit Mcu Keyboard Controller
• Manufacturer: ZiLOG Semiconductor

Port 2 (P27-P20). Port 2 is an 8-bit, bit programmable, bi-
directional, NMOS compatible I/O port. These eight I/O
lines are configured under the software control program
for I/O. Port 2 can be programmed as bit-by-bit indepen-
dently, as input or output, or configured to provide open-
8
(a) Ports P20-P23
(b) Ports P24-P25
(c) Ports P26-P27
Open-Drain
Open-Drain
Open-Drain
OEN
OEN
OUT
OUT
IN
OEN
IN
OUT
IN
Figure 7. Port 2 Configuration
Z8615
Input
Input
Input
drain outputs (Figure 7). P26 and P27 have 2.4 Kohms
( 25%) pull-up resistors and are capable of sourcing
2.4 mA. P24 and P25 have 10.4 Kohms ( 35%) pull-up
when configured as inputs.
Port 2
(I/O)
10.4 Kohms
2.4 Kohms
Pad
Pad
Pad
Z08617 NMOS Z8
K
EYBOARD
®
C
8-B
ONTROLLER
IT
MCU