I was under the impression that this was a pretty fast and highly capable board, but am learning this seems to be a two sided coin.
It seems that while the clock speed is fast, which is be good for calculations and such, it can be pretty slow to actually interact with the outside world. For instance, I was just reading a thread on here that indicated there are zero interrupts which aren't behind I2C, and they carry a 400us+ response time? (On the PMC at least.)
Is that something that can be overcome if I developed my own I/O board for the H7, and by how much? I planned on having an I/O board developed if this thing can function for prototyping anyway, so that's no big deal, but given what I'm learning, it may be a non-starter, or at least severely limit the encoder resolution at high speeds even for prototyping, so any input here would be appreciated.
How fast are the encoder registers? I need to monitor two 2400 pulse per inch encoders at 11 feet per second. (25 feet per second is the ultimate goal, but at those speeds the encoder will likely be 1/4 - 1/8 the resolution) Then trigger an interrupt on a change state, and then provide an output at a specified distance from there (~18 inches or less) as accurately as possible, while performing several other functions such as calculating the real time encoder speed, turning on / off a cooling motor and simple counting of the the sensor triggers and such while feeding the relevant info to an HMI via RS232 / RS485.
Given this, and my (admittedly spotty math) says I'll only be able to register a sensor trigger within ~150+ encoder pulse accuracy, even with an interrupt on the PMC. On the output side, how fast / slow is the response, if I try to change a pin state, am I going to be looking at another ~400us before the pin actually changes?
Thoughts?