Z86D7308HSC datasheet(25/92 Pages) ZILOG

25 / 92 page

Z86D73

40/44/48-Pin Low-Voltage IR OTP

PS019402-1103

XTAL1 Crystal 1 (Time-Based Input)

This pin connects a parallel-resonant crystal, ceramic resonator, LC, or RC net-

work to the on-chip oscillator input. Additionally, an optional external single-phase

clock can be coded to the on-chip oscillator input.

XTAL2 Crystal 2 (Time-Based Output)

This pin connects a parallel-resonant, crystal, ceramic resonant, LC, or RC net-

work to the on-chip oscillator output.

R/W Read/Write (Output, Write Low)

The R/W signal is Low when the CCP is writing to the external program or data

memory.

R/RL (Input)

This pin, when connected to GND, disables the internal ROM and forces the

device to function as a ROMless Z8.

When left unconnected or pulled high to VCC, the part functions

normally as a Z8 ROM version.

Port 0 (P07–P00)

Port 0 is an 8-bit, bidirectional, CMOS-compatible port. These eight I/O lines are

configured under software control as a nibble I/O port or as an address port for

interfacing external memory. The output drivers are push-pull or open-drain con-

trolled by bit D2 in the PCON register.

For external memory references, Port 0 can provide address bits A11–A8 (lower

nibble) or A15–A8 (lower and upper nibble), depending on the required address

space. If the address range requires 12 bits or less, the upper nibble of Port 0 can

be programmed independently as I/O while the lower nibble is used for address-

ing. If one or both nibbles are needed for I/O operation, they must be configured

by writing to the Port 0 mode register. After a hardware reset, Port 0 is configured

as an input port.

Port 0 is set in the high-impedance mode (if selected as an address output), along

with Port 1 and the control signals AS, DS, and R/W through P3M bits D4 and D3

(see Figure 10).

A ROM mask option is available to program 0.4 VDD CMOS trip inputs on P00–

P03. This option allows direct interface to mouse/trackball IR sensors.

Note:

Z86D7308HSC Datasheet(PDF) 25 Page - Zilog, Inc.