On 7/22/2019 1:01 AM, justin White wrote: > > For the Sserial thing, I did eventually get MK to dump a logfile that > showed HM2 come up. SSerial is being initiated as far as that goes, it does > print the version. I tried rigging up a Serial cable and sniffing the > transmit line but the 2.5m baud rate that sserial claims is too high for > anything I'm using to catch. With a scope I can catch the transmit line get > pulled low for a very short period. PCW did mention this: > > I still suspect a wiring error as the most like cause of non-detection of >> SSerial remotes, >> but another possibility is an incorrect CLKMED value in the firmware source >> (The baud rate calculations that the SSerial processor does depend on this >> constant >> matching the actual CLKMED clock rate) > > I've checked the wiring, and double checked the PCB traces against the > datasheets and continuity to every solder joint everything looks fine. > Later in the week I'll be able to test a better circuit but I'm not sure > what to do about checking the clock rate.
The sure way to check is capture a few bytes being sent over the serial port when the driver starts up. That will tell you the *REAL* baud rate. The "medium" clock rate is typically defined in the "card" VHDL file. I'm not sure if there's one specifically for the DE10 or if it uses the one for the DE0_Nano: https://github.com/machinekit/mksocfpga/blob/master/HW/hm2/config/DE0_Nano_SoC_DB25/DE0_Nano_SoC_DB25_card.vhd#L73 The clock source also needs to match the frequency specified in the above file. For the DE0_Nano, the 100 MHz medium clock is generated by an HPS PLL: https://github.com/machinekit/mksocfpga/blob/master/HW/QuartusProjects/DE0_Nano_SoC_DB25/DE0_Nano_SoC_DB25.vhd#L277 -- Charles Steinkuehler [email protected] -- website: http://www.machinekit.io blog: http://blog.machinekit.io github: https://github.com/machinekit --- You received this message because you are subscribed to the Google Groups "Machinekit" group. To unsubscribe from this group and stop receiving emails from it, send an email to [email protected]. To view this discussion on the web visit https://groups.google.com/d/msgid/machinekit/1297e78c-e0b9-c264-e912-9a2cdfff998e%40steinkuehler.net.
