Z86318 Datasheet, PDF (9/26 Pages) Zilog, Inc. – Z8 MCU 8-BIT MICROCONTROLLER

Z86318
Z8^® MCU 8-Bit Microcontroller
PIN FUNCTIONS
XTAL1, XTAL2. Crystal in, crystal out (time-based input Port 0 (P02-P00). Port 0 is a 3-bit, I/O programmable, bi-
1 ^{and output, respectively). These pins connect a parallel- directional, CMOS-compatible I/O port. These three I/O}
resonant crystal, LC, or an external single-phase clock (4 lines can be configured under software control to be input
MHz Max.) to the on-chip clock oscillator and buffer. Note: or output (see Figure 5). When Port 0 is configured as an
XTAL1 has a pull-down resistor.
input port, all lines have the capability to be globally con-
figured (ROM mask option) for a 100K pull-down or pull-up
resistor. The pull-up/pull-down resistor can be disabled as
well. (No current is drawn if disabled.) Graphs showing
current versus pin voltage are shown in Figures 6 and 7.
/OEN
Out
In
Pull-Up
Enable
Pull-Down
Enable
Pad
Figure 5. Port 0 Configuration
PRELIMINARY
9