Hi Loren - I am currently building the B40 but I am a few days behind you (looking at the pace of my building and my projection of free time). If you don't mind, I have a quick question for you.?

I noticed that there is a place for a capacitor (C14) on the board but there is no mention of C14 in the bill of materials, or on the schematic or in any of the other documentation. There is an electrolytic capacitor shown in one? photos and it looks like it simply connects from the the DC source to ground to dampen any voltage fluctuations. Is that right? What value, if any, for C14 did you use??

I'll wait patiently until Jack returns from vacation to hear about the rotary encoder or I may try to figure it out in the meantime.?

Thanks and 73,
-Rob
N4MN

Hi Rob,
C14 is a 100uF electrolytic cap.?

Good luck and 73,

Loren

Hi Loren - thanks for the information on the cap. I don't have one in and it seems to work fine. I'll keep an eye on it though.

I have been looking at how to hook up the RTC and connect it to the SPI bus. It looks like the?AD9850 uses the SPI bus. From the code CLK should connect to D52, MOSI should connect to D51 and then the code defines the Chip Select (SS) as being on D53 (RTCCHIPSELECT). However when I hook up those connections and enable the RTC, I see the clock - but the time is not correct. It's all zeros in 2000. So clearly I'm doing something wrong.

Maybe someone else in the forum here knows how to hook up the DS3234.

73,
-Rob
N4MN

Okay, I figured it out. I was close. The AD9850 only uses the MOSI because it is writing the frequency on the bus. The RTC uses the MISO because it is reading the clock information from the bus. On the Mega 2560 the MISO is the D50 pin. So to recap, connect the pins like this:

GND -> GND
VCC -> +5v
SQW -> not used
CLK -> D52
MISO -> D50
MOSI -> D51
SS ->? D53

Pins D50 - D53 are on the bottom of the board near TP4 (see below).?

There was also another thread (sorry, don't recall number) detailing the real fix: the "complement" operator (~) before each color 'int' value. It would seem some sketches had that operator removed.

73 de ZL2DEX

I put in a little debugging in the?ShowTimes() function and it looks like the time starts out okay (the first entry in the serial monitor) but then immediately the seconds drop off (see below). I think the garbage is coming from these uninitialized pieces of memory in the DateTime variable, it is probably coming from the?secondsBuff variable on or about line 1295.

?

After some code investigation, I discovered that the RTC does not use an interrupt, the clock is polled and updated every time though the Arduino loop which turns out to be between 4 - 6 per second with debugging turned on (it's probably more often with debugging turned off).

I added some code that only updates the RTC only once per second (or very close to once per second) and that seemed to help out the responsiveness of the rotary encoder although if I kept turning the knob, the frequency display would miss a few increments because the Arduino was updating the clock. Perhaps Jack will have some suggestions when he returns from vacation.

73,
-Rob
N4MN

Hi,

?

I am just getting back into the B40 stuff. I like the clock idea, but.

?

Why use the SPI bus RTC clocks, when there are tons of I2C RTC clocks out there ( I’ve got at least 5 or 6 RTC I2C’s laying around)? I’ve used the I2C bus RTC clocks for years in arduinos and they work great even in interrupt based code for arduinos. Was there some sort of design need for it? I am just curious. ??Might play around and change Jack’s code to see if it works, but I do not want to start another code path.

?

73,

开云体育

I came up with the idea of adding a RTC but onlyJack can respond as to why he chose SPI. Maybe have an option?

Bill, VK7MX