SAB80515 Datasheet, PDF (108/270 Pages) Siemens Semiconductor Group – 8-Bit Single-Chip Microcontroller Family

On-Chip Peripheral Components
7.8.2.1 Driving the SAB 80515/80535 from External Source
For driving the SAB 80515/80535 from an external clock source, the external clock signal is to be
applied to XTAL2. A pullup resistor is recommended to increase the noise margin, but is optional if
the output high level of the driving gate meets the V_IH1 specification of XTAL2.
XTAL1 has to be connected to ground (see figure 7-50).
Figure 7-49
On-Chip Oscillator Circuitry
Figure 7-50
External Clock Source
Semiconductor Group
108