For those old timers who have had the chance to work with the Intel 8-bit microcontrollers and ever needed to generate PWM would remember how tedious things got at times, they would either have to do software based bit-bang or utilize a timer with an interrupt service routine to perform the actual PWM. Which is easy for one PWM channel, but becomes complicated when you have a requirement to have more than two PWM channels. Mainly because you only have two timers.
I remember looking at the Intel MCS-96 datasheets in the 1990s and admiring the fact that the more expensive 16-bit controller family had the HSO/HSI (High speed output/input) capability. But the parts were honestly beyond the reach of a student or hobbyist. The programming algorithm was also not very learner friendly, okay may be Quick Pulse was an improvement but still the devices were beyond the reach of a beginner.
This got me thinking, what if Intel had provided HSI/HSO in the 1980s in their 8-bit MCS-51? The maker revolution that was started by AVR microcontrollers could have been started 20 years sooner… Just thinking out loud.
I found the Atmel 89C2051/4051 family really useful and convenient to use for a hobbyist, could they have added some dedicated PWM capability into the product? It would have been possible but then you would possibly undermine what the AVR revolution was bringing to the table.
Enough rambling for the day, here are some links/docs that you might find useful for reference. They are only provided for editorial purposes and are copyright of their respective publishers.