Re: #qcx Firmware version 1.02 release #qcx

Guido PE1NNZ

Hi Hans!

It was very good to meet you in person last Saturday on the VERON day, and thank you very much to have some follow up on the LCD_RS pin sharing topic we discussed and the related woodpecker interference. 

Wow, what an improvement with T1.02, the woodpecker is completely gone. But I also got stuck with a blank screen initially, and it was not because of firmware issues; after replacing the older LCD with a newer one (exactly identical one) the display worked correctly.

Are you giving the RS pulse just after the data is settled?


On Friday, November 8, 2019, Hans Summers <hans.summers@...> wrote:
Hi Aug

You definitely have trouble with at least one of your fingers but I am glad to hear that 1.02a is working fine for you now. 

Awaiting some other reports too please, from anyone who had blank display on 1.02. 

So I imagine what happened, is variations in batches of LCD modules. I make QCX kits these days in batches of 1000 at a time and the LCD modules are custom-manufactured specially for me. If you look at the right side of the module you will see that there are two LEDs. The cheaper blue/white eBay AliExpress etc LCD modules have only one LED. At one point I was considering switching to the common type, to lower my costs. But I compared the two side-by-side under identical conditions and the difference in display quality was quite significant, plenty to convince me to stay with my nice custom-made ones. But... I digress... I expect what happened was just minor variation in components from one batch to another. The aggressive short pulse I used in 1.02 must have been just a bit on the too-aggressive side. So now in 1.02a it is a couple of CPU cycles longer, enough to keep all the LCDs happy. This is my theory :-)

Two points to note:

1) The "woodpecker" is still cured, both with the too short pulse and the less short pulse

2) The shortened pulse was the LCD_E signal which clocks in the data to the LCD. In 1.02a the pulse length on this signal is the same as it was in all previous firmware versions. Therefore if the theory about pulse length is correct, there is NO risk that the length will still not be enough - because now it is the same as it was previously. The LCD_RS signal is put to low after clocking in the data with LCD_E, just the same as in 1.02. 

For anyone who ordered a QCX, or an upgrade chip... don't worry... we didn't send them yet :-D   For some reason age and experience led to slight alterations in default characteristics, including increased levels of PESSIMISM, so I had decided to wait a day or two to see if anything like this happened ;-)

Any other feedback on 1.02a? If nothing else is reported amiss, I will ship out all the orders on Monday. Using 1.02a. 

73 Hans G0UPL

On Fri, Nov 8, 2019 at 6:39 AM August Treubig <atreubig@...> wrote:
Finger Graphical Error  
no longer blank with !.02a..


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