I got the chip from a blog elsewhere (https://cpldcpu.wordpress.com/2019/08/12/the-terrible-3-cent-mcu/ https://cpldcpu.wordpress.com/2019/08/12/the-terrible-3-

I got the chip from a blog elsewhere (https://cpldcpu.wordpress.com/2019/08/12/the-terrible-3-cent-mcu/ https://cpldcpu.wordpress.com/2019/08/12/the-terrible-3-cent...), advertised as a 8.75-cent MCU. I did a brief search before posting, and one webpage suggested a 1000+ quantity price for $0.11 USD. However, upon closer inspection, this webpage is completely out-of-stock. (https://www.lcsc.com/product-detail/Others_Holtek-Semicon-HT68F001_C133382.html https://www.lcsc.com/product-detail/Others_Holtek-Semicon-HT...). I assumed the ~10-cent price point was still available and should have looked more into it before posting. > Holtek 'Buy Online' shows $1.50 @ 500+ That is indeed terrible. ATTiny4 chips (cheapest chip on Digikey that's available... 512B Flash + 32B RAM) are available at 39-cents @100 Quantity from Digikey, so these HT68F001 chips need to come in significantly cheaper than the ATTiny4 before I consider them. Sure, the ATTiny4 is like 20 uA at 128kHz, but this is all less than the leakage current of batteries, so we're definitely looking at multi-year battery lives. Also PWM, Analog Comparator, ADCs, and other such features are included. So its more capable. In 2019, the HT68F001 _WAS_ a 8.75-cent chip or so. Alas, the 2020+ chip shortage may have killed the cost-effectiveness of this particular model.