8XC196MC, MD, MH USER’S MANUAL

To enable the interrupts, set the corresponding mask bits in the mask register (see Table 9-2 on page 9-3) and execute the EI instruction to enable interrupt servicing. You can read the interrupt pending register to determine whether there are any pending interrupts. Refer to Chapter 5, “Stan- dard and PTS Interrupts” for details.

9.7DESIGN CONSIDERATIONS

This section describes design and programming considerations for using the waveform generator.

9.7.1Dead Time and Duty Cycle

Short dead times have little effect on the duty cycle if the pulse is relatively wide; however, longer dead times with narrower pulses can affect the duty cycle (Figure 9-14). No minimum pulse width is imposed by the hardware, so it is possible to deassert an output for the entire period if the total dead time is greater than the pulse width. For this reason, software should ensure that the pulse width is at least 3 × T DEAD.

WG_COUNT

 

 

1

 

 

WG_COUNT=

Dead Time

Dead Time

WG_COMP

Increased

Increased

Dead Time

 

 

(DT)

 

 

WFG

 

 

P6.0 / WG1#

 

 

=DT x WFG#

 

 

P6.1 / WG1

 

No WFG1 Output

=DT x WFG

 

 

 

Mode 0, OP0 = OP1 = 1, PH1.0 = PH1.1 = PH1.2 = 1

= Power Output Driver Enabled

= Dead Time

 

 

A2660-01

Figure 9-14. Effect of Dead Time on Duty Cycle

9-20

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Intel 8XC196MD, 8XC196MH, 8XC196MC manual Design Considerations, Dead Time and Duty Cycle, Wgcount WGCOUNT=, Wgcomp, Wfg