I managed to get a few free samples of the PCF8574N from TI.? It is an I/O expander I2C - 8bits in a 16DIP package.? It is basically the chip used on the I2C LCD piggyback boards. I keep you posted.
On Thu, Apr 19, 2018 at 12:03 PM, Gerry Hull
<gerry@...> wrote:
Understood.? I¡¯m wanting to put transverters in my ubitx; would love to control the I/O switching, as well as have the display show the transverted frequency. So, these would not be signals that needed to be switched rapidly. ? I would not use it to key CW, but I might use these I/Os for a keying sequencer.
Gerry, W1VE
On Thu, Apr 19, 2018 at 12:45 PM Jerry Gaffke via Groups.Io <jgaffke=
[email protected]> wrote:
Could work fine.
The library to speak i2c is already getting loaded for the si5351.
Primary issue I see is that i2c links take a millisecond or so,
vs under a microsecond for direct access of an IO pin.
At some point as we load up the Nano with i2c peripherals, it will get bogged down.
This applies to i2c displays as well.
Hasn't been an issue yet.
Another possible issue is that the common i2c bus provides an easy way
for RFI and birdies to find their way into the receiver.
Jerry, KE7ER
On Thu, Apr 19, 2018 at 09:28 am, Mark Kesner wrote:
Looks like a great idea to me.? I googled the mentioned boards and there is a lot of info on how to use these.? Sparkfun has breakout boards for a similar device for $5 as well as examples and links to the library, etc.
I guess it depends on the firmware you are using and whether there is room to load the library. (?)
Thanks!
Mark
KC4GIA
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Paul Mateer, AA9GG
Elan Engineering Corp.
NAQCC 3123, SKCC 4628
AA9GG