EM78P259N/260N

8-Bit Microprocessor with OTP ROM

When an interrupt is generated by the High time down counter underflow (if enabled), the next instruction will be fetched from Address 018 and 01BH (High time and Low time, respectively).

6.8.2 Function Description

The following figure shows LGP=0 and HF=1. The IROUT waveform modulates the Fcarrier waveform at low time segments of the pulse.

Fcarrier

 

 

 

low time width

high time width

low time width

high time width

HF

 

 

 

start

 

 

 

IRE

 

 

 

IROUT

 

 

 

Fig. 6-12a LGP=0, HF=1, IROUT Pin Output Waveform

The following figure shows LGP=0 and HF=0. The IROUT waveform cannot modulate the Fcarrier waveform at low time segments of the pulse. So IROUT waveform is determined by the high time width and low time width instead. This mode can produce standard PWM waveform

Fcarrier

 

 

 

low time width

high time width

low time width

high time width

HF

 

 

 

start

 

 

 

IRE

 

 

 

IROUT

 

 

 

Fig. 6-12b LGP=0, HF=0, IROUT Pin Output Waveform

52 •

Product Specification (V1.2) 05.18.2007

(This specification is subject to change without further notice)

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Image 58
IBM EM78P259N/260N manual Function Description, Fcarrier