T
Theo Markettos
Guest
Antti <antti.lukats@gmail.com> wrote:
To follow up...
In the end I went with putting a connector with the WaveShare pinout for my
board. After all my other pins were done I had 10 pins spare, consisting of
8 I/Os and 2 inputs to spare. That pretty much constrained the pinout, and
the need to hardwire power pins to particular places sealed the rest.
(I also had 8 analog inputs I didn't need - it's possible to abuse the ADC
to make those ~100KHz digital inputs, but that's of limited use)
To summarise the dicussion:
* A number were for boards containing FPGAs. I have the FPGA, I was looking
for a system for accessory modules to plug into the FPGA board. Perhaps
this was unclear from the question.
* All the systems mentioned were tied to a particular board vendor.
* I think the system with the biggest following behind it is Pmod, which at
least has non-Digilent modules. But at 4 I/Os it's quite limited - it's
really in SPI/I2C territory, which means low speed 'sensors' rather than
higher speed I/O.
* xkcd.com/927
I'm still most interested in an Arduino-like standard for FPGAs boards:
* Something that scales to variable numbers of I/Os without pain (so you can
attach an SPI thing or a PCI socket to the same connector)
* That copes with both high and low speed devices (eg a cheap slow connector
with an optional more expensive addon for transceivers)
* That has a similar kind of following to it as Arduino does:
- Multi-vendor (so more than one organisation sell boards to that form
factor)
- Multi-platform (so will work on multiple FPGA vendors)
- Has some degree of ecosystem around it (eg example code exists)
* That isn't tightly tied to the limitations of one platform (eg the need to
put a microcontroller on the Arduino 'shield' because the main Atmega
can't cope)
Perhaps we need FPGA to be more mainstream for this to take off, I don't
know...
Theo
To follow up...
In the end I went with putting a connector with the WaveShare pinout for my
board. After all my other pins were done I had 10 pins spare, consisting of
8 I/Os and 2 inputs to spare. That pretty much constrained the pinout, and
the need to hardwire power pins to particular places sealed the rest.
(I also had 8 analog inputs I didn't need - it's possible to abuse the ADC
to make those ~100KHz digital inputs, but that's of limited use)
To summarise the dicussion:
* A number were for boards containing FPGAs. I have the FPGA, I was looking
for a system for accessory modules to plug into the FPGA board. Perhaps
this was unclear from the question.
* All the systems mentioned were tied to a particular board vendor.
* I think the system with the biggest following behind it is Pmod, which at
least has non-Digilent modules. But at 4 I/Os it's quite limited - it's
really in SPI/I2C territory, which means low speed 'sensors' rather than
higher speed I/O.
* xkcd.com/927
I'm still most interested in an Arduino-like standard for FPGAs boards:
* Something that scales to variable numbers of I/Os without pain (so you can
attach an SPI thing or a PCI socket to the same connector)
* That copes with both high and low speed devices (eg a cheap slow connector
with an optional more expensive addon for transceivers)
* That has a similar kind of following to it as Arduino does:
- Multi-vendor (so more than one organisation sell boards to that form
factor)
- Multi-platform (so will work on multiple FPGA vendors)
- Has some degree of ecosystem around it (eg example code exists)
* That isn't tightly tied to the limitations of one platform (eg the need to
put a microcontroller on the Arduino 'shield' because the main Atmega
can't cope)
Perhaps we need FPGA to be more mainstream for this to take off, I don't
know...
Theo