3 ms·

I can't seem to get the datasheets (getting 404s after I finally dove into the "Community" section of their website which seems to be where they stash the docum

by bsder 3y ago

I can't seem to get the datasheets (getting 404s after I finally dove into the "Community" section of their website which seems to be where they stash the documentation), no mention of real-time with the few diagrams showing an arbitrated bus (which is anathema to real-time), no availability (can't buy chips from anywhere including LCSC), and low-power current specifications almost an order of magnitude larger than any competitor. Yeah, I'm not surprised I haven't heard of them.

snvzz 3y ago
>I can't seem to get the datasheets For which chip family? e.g. BLxxx ones are infamous for lack of docs and I avoid them for that reason, but I haven't had trouble with CH32V family or ESP32-C family. >getting 404s after I finally dove into the "Community" section of their website which seems to be where they stash the documentation), Oh, do you perhaps mean the CV1800B used in Milk-V Duo? They changed the path in the repository, I found it[0] by visiting the parent in the URL's path. Whoever maintains the wiki should either not have linked the blob but the repository, or should have used an actual commit instead of master for the blob. It's preliminary, but has some 700 pages already (!). https://github.com/milkv-duo/duo-hardware/tree/main/CV1800B https://github.com/milkv-duo/duo-hardware/tree/main/CV1800B
- bsder 3y ago
  Yeah, it was the BLxxx family I was looking at. I'll look at the CH32V family. As for the CV1800B, I note that it has an 8051 in the RTC domain. Which misses the whole bloody point of RISC-V. > It's preliminary, but has some 700 pages already (!). Then they've only got another 4300 pages to go ... :) (By comparison: see the AM3359 Technical Reference Manual from TI which is 5100 pages long).
  - snvzz 3y ago
    >(By comparison: see the AM3359 Technical Reference Manual from TI which is 5100 pages long). It looks that much larger and much more complex design. It's also been around for a while, having released in 2011. Unsurprisingly, a significant amount of pages are used to describe the CPU, interrupt controller, memory management and other such ARM-specific cruft. In contrast, RISC-V is much simpler, cleaner, and much more thoroughly standardized, thus the vendor can simply point to the relevant RISC-V specs. >Then they've only got another 4300 pages to go ... :) At least you are just joking :) The less the documentation needed to describe the same functionality the better. Simplicity is valuable on its own, thus complexity needs be justified.
    - bsder 3y ago
      > In contrast, RISC-V is much simpler, cleaner, and much more thoroughly standardized, thus the vendor can simply point to the relevant RISC-V specs. I doubt it. Even simple questions like "How many clock cycles to access SPI register X?" wind up surprisingly complicated. And the manufacturer needs to document all of it because there just aren't enough users to figure it all out by experiment. Even if your CPU is 100% bog standard (and these are not), documenting the peripherals takes a ton of work. Datasheets, in general, tend to be horrible. However, I find that the Chinese datasheets are particularly dreadful whether the chips are simple or complex.

by bsder 3y ago

snvzz 3y ago

>I can't seem to get the datasheets For which chip family? e.g. BLxxx ones are infamous for lack of docs and I avoid them for that reason, but I haven't had trouble with CH32V family or ESP32-C family. >getting 404s after I finally dove into the "Community" section of their website which seems to be where they stash the documentation), Oh, do you perhaps mean the CV1800B used in Milk-V Duo? They changed the path in the repository, I found it[0] by visiting the parent in the URL's path. Whoever maintains the wiki should either not have linked the blob but the repository, or should have used an actual commit instead of master for the blob. It's preliminary, but has some 700 pages already (!). https://github.com/milkv-duo/duo-hardware/tree/main/CV1800B https://github.com/milkv-duo/duo-hardware/tree/main/CV1800B

bsder 3y ago
Yeah, it was the BLxxx family I was looking at. I'll look at the CH32V family. As for the CV1800B, I note that it has an 8051 in the RTC domain. Which misses the whole bloody point of RISC-V. > It's preliminary, but has some 700 pages already (!). Then they've only got another 4300 pages to go ... :) (By comparison: see the AM3359 Technical Reference Manual from TI which is 5100 pages long).
- snvzz 3y ago
  >(By comparison: see the AM3359 Technical Reference Manual from TI which is 5100 pages long). It looks that much larger and much more complex design. It's also been around for a while, having released in 2011. Unsurprisingly, a significant amount of pages are used to describe the CPU, interrupt controller, memory management and other such ARM-specific cruft. In contrast, RISC-V is much simpler, cleaner, and much more thoroughly standardized, thus the vendor can simply point to the relevant RISC-V specs. >Then they've only got another 4300 pages to go ... :) At least you are just joking :) The less the documentation needed to describe the same functionality the better. Simplicity is valuable on its own, thus complexity needs be justified.
  - bsder 3y ago
    > In contrast, RISC-V is much simpler, cleaner, and much more thoroughly standardized, thus the vendor can simply point to the relevant RISC-V specs. I doubt it. Even simple questions like "How many clock cycles to access SPI register X?" wind up surprisingly complicated. And the manufacturer needs to document all of it because there just aren't enough users to figure it all out by experiment. Even if your CPU is 100% bog standard (and these are not), documenting the peripherals takes a ton of work. Datasheets, in general, tend to be horrible. However, I find that the Chinese datasheets are particularly dreadful whether the chips are simple or complex.