The “terrible” 3 cent MCU – a short survey of sub $0.10 microcontrollers

Post by tomcam » Tue, Aug 13, 2019, 9:08 PM UTC

dbcurtis wrote: post #3

These have their uses. A friend who frequently does contract development in the toy space has (or at least used to have) a favorite go-to MCU that costs under $0.06 in bare die. It is essentially a 6502 with 100 bytes of RAM and a metric butt-load of mask-programmable ROM. It was originally designed for greeting cards. He has designed it into toys. It is hard to use, you need a dev kit and a good relationship with th…

Post by vardump » Tue, Aug 13, 2019, 9:09 PM UTC

petra wrote: post #31

ChuckMcM wrote: post #2

It is interesting that its possible to produce chips at this price for more than a short time period. Also that they are all basically PIC clones or variants speaks to the core competency of these companies is manufacturing and operational efficiency, not MCU design. I think a fascinating experiment here would be to invest some time in an unencumbered scalable design that could be implemented very inexpensively (say…

Here's this experiment sort-of running: WCH, which sells cheap mcu's(like $0.25 8051-mcu with usb/16Kflash) is working on a risc-V bluetooth mcu: https://www.cnx-software.com/2019/02/16/wch-ch572-risc-v-mcu... And since risc-v has versions somewhere around 5K-10K gates, well, a lower end mcu isn't far, probably. Still, it would be interesting to think how we can get from that, to standard peripherals, and standard pi…

Post by a1369209993 » Tue, Aug 13, 2019, 9:13 PM UTC

benj111 wrote: post #20

dbcurtis wrote: post #3

These have their uses. A friend who frequently does contract development in the toy space has (or at least used to have) a favorite go-to MCU that costs under $0.06 in bare die. It is essentially a 6502 with 100 bytes of RAM and a metric butt-load of mask-programmable ROM. It was originally designed for greeting cards. He has designed it into toys. It is hard to use, you need a dev kit and a good relationship with th…

"metric butt-load of mask-programmable ROM" What would that be in this context? I'm guessing we're talking KB rather than TB?

Post by petra » Tue, Aug 13, 2019, 9:18 PM UTC

vardump wrote: post #43

petra wrote: post #31

Earlier quoted context omitted.

Here's this experiment sort-of running: WCH, which sells cheap mcu's(like $0.25 8051-mcu with usb/16Kflash) is working on a risc-V bluetooth mcu: https://www.cnx-software.com/2019/02/16/wch-ch572-risc-v-mcu... And since risc-v has versions somewhere around 5K-10K gates, well, a lower end mcu isn't far, probably. Still, it would be interesting to think how we can get from that, to standard peripherals, and standard pi…

> And since risc-v has versions somewhere around 5K-10K gates, well, a lower end mcu isn't far, probably. 5-10k? Seriously? That's amazing. Z80 had 8500. According to Wikipedia, even truly simple and bare bones 6502 had 3510 or 3218.

Post by vardump » Tue, Aug 13, 2019, 9:19 PM UTC

petra wrote: post #47

vardump wrote: post #43

Earlier quoted context omitted.

> And since risc-v has versions somewhere around 5K-10K gates, well, a lower end mcu isn't far, probably. 5-10k? Seriously? That's amazing. Z80 had 8500. According to Wikipedia, even truly simple and bare bones 6502 had 3510 or 3218.

Smallest irsc-v core i know: https://devhub.io/repos/kammoh-picorv32 ~1000 Luts. 1 Lut = 6-24 gates on average. a bit pmore but still pretty close.