3 ms·

That was my reaction, too :-). My day job for 4 years was writing a software-defined radio for aviation on a Blackfin-based system. Intel and ADI made some real

That was my reaction, too :-). My day job for 4 years was writing a software-defined radio for aviation on a Blackfin-based system. Intel and ADI made some really unfortunate design choices with that architecture that ADI seems surprisingly unwilling to correct.

diydsp 11y ago
Any details you can share? I mostly don't use ADI due to closed compilers, but I had many fond experiences with 21xx and made one epic project with an early Blackfin.
- coderjames 11y ago
  My single biggest pain point was the single-buffered UARTs in the 53X series. On the BF-538 that we were using, there are three of them and we needed them all. Since each one can only buffer a single incoming or outgoing byte at a time, there's a lot of interrupt-handling overhead with all of the RISC-style registers that need to be saved on each incoming byte. We were already using two of the SPORTs and both DMA engines for hard real-time transmit and receive signal processing with microsecond-scale deadlines, so they weren't available to offload the UARTs. But since the UARTs have such tiny hardware buffers, their interrupts have to be very high priority in order to avoid dropping characters. On a different project we were trying to build a very-low-power system around one of their new (at the time) BF52X parts, which had new low-power states for extended sleep. Except in the 0.0 version of the chips, those low-power states simply didn't work. An updated errata sheet was published a week or two later documenting that the processor couldn't be woken up once put to sleep.
  - diydsp 11y ago
    Ugh! Single buffered UARTS are catastrophic and outdated. sorry you had to go through that. ADI is more about raw processing power in base station apps; they don't seem to be interested in embedded, sigh. Thank you for getting back to me.
themanfrommars 11y ago
Yup, those errata lists....

diydsp 11y ago

Any details you can share? I mostly don't use ADI due to closed compilers, but I had many fond experiences with 21xx and made one epic project with an early Blackfin.

coderjames 11y ago
My single biggest pain point was the single-buffered UARTs in the 53X series. On the BF-538 that we were using, there are three of them and we needed them all. Since each one can only buffer a single incoming or outgoing byte at a time, there's a lot of interrupt-handling overhead with all of the RISC-style registers that need to be saved on each incoming byte. We were already using two of the SPORTs and both DMA engines for hard real-time transmit and receive signal processing with microsecond-scale deadlines, so they weren't available to offload the UARTs. But since the UARTs have such tiny hardware buffers, their interrupts have to be very high priority in order to avoid dropping characters. On a different project we were trying to build a very-low-power system around one of their new (at the time) BF52X parts, which had new low-power states for extended sleep. Except in the 0.0 version of the chips, those low-power states simply didn't work. An updated errata sheet was published a week or two later documenting that the processor couldn't be woken up once put to sleep.
- diydsp 11y ago
  Ugh! Single buffered UARTS are catastrophic and outdated. sorry you had to go through that. ADI is more about raw processing power in base station apps; they don't seem to be interested in embedded, sigh. Thank you for getting back to me.

themanfrommars 11y ago

Yup, those errata lists....