Small footprint USB

[funkathustra]

QSOP24 is still a bit larger than the TSSOP20 STM32F042F6 though...

Don't forget the 3.3V regulator you'll need with the ST part that you won't need with the EFM8 when figuring sizes...

[technix]

QSOP24 is still a bit larger than the TSSOP20 STM32F042F6 though...

Don't forget the 3.3V regulator you'll need with the ST part that you won't need with the EFM8 when figuring sizes...

I am semi persuaded here. Simplicity Studio does work under macOS. J-Link v9 probably will work even with debugging 8051-based chips over SWD (C2D? The signals matches ARM SWD though, and I will very likely keep using the CoreSight pinout even for 8051 since I have already built the ARM 20-pin to CoreSight 10-pin adapter) Now where can I find the chip...?

(P.s. How to get it to use the copy of much newer ARM GCC 6.1 toolchain I installed myself for use with Eclipse instead of the shipped GCC 4.9?)

[funkathustra]

J-Link v9 probably will work even with debugging 8051-based chips over SWD (C2D? The signals matches ARM SWD though, and I will very likely keep using the CoreSight pinout even for 8051 since I have already built the ARM 20-pin to CoreSight 10-pin adapter)

Yeah, C2D is different than SWD; SiLabs worked with Segger to add support to J-Link. Works on the command-line and from within Simplicity Studio.

Now where can I find the chip...?

You're in China, right? I'm in the states, so I don't have access to the Shenzhen markets — my closest option is Taobao. I briefly looked and found some EFM8UB11F16G chips, but I don't see any completed transactions (in my Taobao experience, that's not a good sign). However, it's worth a shot?

Arrow Asia? My Arrow site shows plenty in stock.

You can go through Burnon, EDOM Tech, WT Microelectronics, etc if you want a traditional distributor route.

Newark/Element14/Farnell? They've got a pretty big set-up in HK/China, right? They're not really an SiLabs distributor, but it looks like they can order the part for you.

For what it's worth, the official distributor with the SiLabs linecard is Symmetry Electronics, and they generally have the best pricing, too. They should have no problem shipping to China (no clue on cost, though). Here's the product page for the EFM8UB11F16G.

(P.s. How to get it to use the copy of much newer ARM GCC 6.1 toolchain I installed myself for use with Eclipse instead of the shipped GCC 4.9?)

What does ARM GCC have to do with the EFM8 / 8051 microcontrollers?

Oh, are you talking about doing EFM32 ARM Cortex-M0 development in Simplicity Studio, too? You should be able to make a new toolchain configuration to support that. Leave a message on the Simplicity Studio section of the SiLabs Forums. The SiLabs guys are really helpful, and don't mind helping people "hack" their tools a bit (one employee helped me install all the SiLabs-specific stuff into a stock Eclipse installation --- definitely not intended to be a supported procedure).

[technix]

Now where can I find the chip...?

You're in China, right? I'm in the states, so I don't have access to the Shenzhen markets — my closest option is Taobao. I briefly looked and found some EFM8UB11F16G chips, but I don't see any completed transactions (in my Taobao experience, that's not a good sign). However, it's worth a shot?

Arrow Asia? My Arrow site shows plenty in stock.

You can go through Burnon, EDOM Tech, WT Microelectronics, etc if you want a traditional distributor route.

Newark/Element14/Farnell? They've got a pretty big set-up in HK/China, right? They're not really an SiLabs distributor, but it looks like they can order the part for you.

For what it's worth, the official distributor with the SiLabs linecard is Symmetry Electronics, and they generally have the best pricing, too. They should have no problem shipping to China (no clue on cost, though). Here's the product page for the EFM8UB11F16G.

I am in Shanghai so no Shenzhen market either. The listings on Taobao does not look good to me (I just won’t trust zero sales listings without an actual picture of the part) and on a major Chinese distributor website the entire EFM8 line is nowhere to be seen.

The same for ATSAMD11: nowhere trustworthy to be seen in China. I am even thinking about using CH340T (a SSOP20 variant of the CH340B/C/G that have an active high output pin indicating USB enumeration status) and an STC 8051 chip (that can be reset by CH340T upon USB reenumeration.)

[funkathustra]

...and on a major Chinese distributor website the entire EFM8 line is nowhere to be seen.

Aren't you just building a one-off product? I can drop a few EFM8UB11s in an envelop and mail them to you. Seriously, no big deal.

... and an STC 8051 chip (that can be reset by CH340T upon USB reenumeration.)

What do you need the CH340T for? Doesn't the STC8 have a USB interface? Or is that only for programming? The STC8 only has a Chinese datasheet, so I'm sort of in the dark. Can you read Chinese? Wasn't sure if you were an expatriate or a local native 

Actually, now that I think about it, since you're in China, maybe look at some of the semiconductors originating in the Chinese/Taiwanese markets? Check out the Holtek HT66FB542? 24-pin SSOP package (just make sure to get the proper OCD version for development). I've had good luck buying Holtek stuff on Taobao, but I'm sure you can find it locally, too, as they have good China distribution — at least in Shenzhen (no clue about Shanghai, though). A lot of the Chinese/Taiwanese chips I've used with USB are pretty special-purpose (like for web cams, or whatever), but there should be some general-purpose stuff out there.

Do you have access to Microchip parts? Obviously the PIC16F1454 is a classic choice. I've used that part in a ton of designs.

Otherwise, the STM32F042F4 is a safe bet, and you should be able to buy that just about everywhere (I bet they even have Mars distributors). I'd really look for something with an integrated LDO, though.

Also, as I said, my offer to send you a Treehopper or two is still on the table  . If anything else, you could use it as an EFM8 dev board.