z86c9216vsc ZiLOG Semiconductor, z86c9216vsc Datasheet - Page 25

• Manufacturer Part Number: z86c9216vsc
• Description: Ir Microcontroller
• Manufacturer: ZiLOG Semiconductor

Zilog
Port 2 (P27-P20). Port 2 is an 8-bit, bidirectional, CMOS
compatible I/O port. These eight I/O lines can be indepen-
dently configured under software control as inputs or out-
puts. Port 2 is always available for I/O operation. A mask
option is available to connect eight 200 kOhms ( 50%)
pull-up resistors on this port. Bits programmed as outputs
are globally programmed as either push-pull or open-
drain. Port 2 may be placed under handshake control. In
this configuration, Port 3 lines, P31 and P36 are used as
the handshake controls lines /DAV2 and RDY2. The hand-
DS97LVO0900
Open-Drain
OEN
Out
In
Z86LXX
MCU
Figure 13. Port 2 Configuration
P R E L I M I N A R Y
shake signal assignment for Port 3, lines P31 and P36 is
dictated by the direction (input or output) assigned to Bit 7,
Port 2 (Figure 13). The eight bits of Port 2 are configured
as inputs with open-drain outputs.
Port 2 also has an 8-bit input OR and an AND gate which
can be used to wake up the part (Figure 39). P20 can be
programmed to access the edge selection circuitry (Figure
22).
Port 2 (I/O)
Optional
Handshake Controls
/DAV2 and RDY2
(P31 and P36)
VCC
200 k
PAD
Mask
Option
Z86C72/C92/L72/L92
IR Microcontroller
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