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Re: QMX Build Completed but seems to be some issues

 

Hi all

A little word about what goes on in the firmware should aid understanding and debugging.?

Firstly if you are in firmware update mode, the buck converters are NOT being used. This means there is no 5V rail at all, and the 3.3V rail is supplied by the 78M33 linear voltage regulator.?

Secondly when you are in the main QMX application mode, the program goes through a whole step by step initialization procedure. The bootloader is ALWAYS run, but if there is no flag set in the EEPROM to indicate the user wants to do firmware update, and if the application firmware is present, then it will jump into the application?program very soon after power up. The initialization procedure?of QMX goes through many stages. It's important?to understand the sequence.?
  1. Initialize the Flash memory, reset peripherals, configure the system clock, configure the I/O pins
  2. Initialize the DMA (Direct Memory Access interface)?
  3. Initialize the ADC (Analog to Digital Converter) of the CPU; we use 10 channels for monitoring supply voltage, 3.3V, 5V and Bias buck converter outputs, Fwd/Rev power from the SWR bridge etc; all continuously read via the ADC and stored in memory using DMA
  4. SMPS (Switched Mode Power Supplies) initialization - this means the little plug-in buck converter boards.?
  5. DIsplay init - which initializes the LCD module, switches on the backlight (depending on if you configured that to be on in the configuration menu), and writes the Splash screen text (QMX, firmware version, QRP Labs 2023).?
  6. Blah blah loads and loads of other things - including eventually, the USB initialization...?
  7. Eventually, audio system initialization (the I2S 48ksps stereo ADC chip and corresponding stereo DAC chip
Eventually once all initializations are done (I say eventually but this is all over in less than half a second) - the main process handling runs for the rest of the duration of the radio being powered up, doing all the various functions - one of which is handling a serial terminal login via USB Virtual COM port (PuTTY etc).?

The SMPS initialization actually WAITS until both the 3.3V and 5V buck converters are spun up and producing the correct voltages, and the system has switched over to using the buck converter boards. The 3.3V rail is first, followed by the 5V rail. In that order. The program has GOT to wait because subsequent initializations require the 5V rail to be ready. This includes the LCD module which is powered from the 5V rail, and the 48ksps stereo I2S ADC and DAC chips.?

What I'm saying ladies and gentlemen is that if you are able to log in to your QMX using PuTTY then the program has already gone through its entire initialization successfully. The buck converters have both been powered up and are in use producing the 3.3V and 5V rails. It's already gone past initialization of the ADC/DAC chips which also require the 5V rail.?

So if you have PuTTY log in but nothing on your LCD screen - don't think the problem is the power supplies, it cannot be. The problem can only be some kind of connection problem to the LCD itself. Or perhaps the contrast adjustment needs doing. It should be noted that currently, in common with all other QRP Labs kits, the processor talks AT the LCD, it does not ever try to read anything back from it. If the LCD wasn't even plugged in, the processor would still run through the initialization and tell stuff to the LCD.

I suggest checking all the connections to the LCD module. Which are the 2x5-pin header at the top left of the board and the 2x2 pin header at the top right.?

Note also that the baud rate, start/stop bits etc configuration of PuTTY etc are irrelevant to a Virtual COM Port serial device such as QMX. They are ignored. Not used.?

73 Hans G0UPL



On Thu, Jun 1, 2023 at 3:17?PM Conrad Trautmann - N2YCH via <conradtrautmann=[email protected]> wrote:

I hope it's okay that I join this thread...I'm at about the same point. I copied the firmware file in, powered down and powered back up and now it appears as a port in my device manager, however, I have no display. I tried adjusting the LCD trimmer and nothing. I putty'd in (serial mode, 19200) got to the menu and did a firmware update and copied the file in a second time and waited...it rebooted on its own, but I still have no display.

I read on another thread that the display is dependent on the power supplies which are dependent on the firmware. The microprocessor seems to be acting like it should, so do you think I may have a power supply issue to troubleshoot?

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