COM1 and STANDBY COM1 : 7 Segment Display

[CmteLucasGodoy]

Hello Sim Innovations Team,

I have one question regarding the use of 7 digits segment display.

If I select one frequency with "5" in the end, like "119.405" ,and, after that, I select the frequency "118.400", The SIM Var is, unfortunately changed to "118.4" and not to "118.400". the tostring() converts the output to "118.4" (not completing the zeros missing) and the 7 segment Display displays: "118.405" (with the 05 "not updated from the last selected sequence").

Is there any solution that you already use for this problem?

Thank you in advance,
Lucas Godoy

[Ralph]

Please see our wiki:
https://siminnovations.com/wiki/index.p ... _now_works!

So in your case for example string.format("%07.03f", frequency)

[Keith Baxter]

Hi,

Firstly, what 7 seg display are you using and how is it wired?

For a max7219 8 digit display you would have to format the string something like this. But that depends on the display and shift register.

string.format("% 9.03f",(com1act/1000))
The string format forces % 9 digits which includes the decimal. the .03f forces 3 decimal places.

Keith

[Ralph]

Depends indeed on which module you use. But you can also just add a few spaces, depending on where you want the frequency.
Example for a 8 character display and two spaces 'in front': string.format(" %07.03f", frequency)

[Keith Baxter]

So in your case for example string.format("%07.03f", frequency)

Hi,

We have to be careful with string.format() when it comes to 7seg displays.
The code you quoted assumes a LEFT address.

What happens if the value is 23.005 instead of 123.005
23.005 would return 023.005 + two white spaces addressed to the left most digit.

What you will find when running this simple code is the difference as to what the 0 and white-space. The string.format("%07.03f"forces a left align and will leave white-spaces after the three decimals, whereas string.format("% 7.03f") forces a right align but only to the 6th digit.
To force a right align on a 8 digit max7219 you must use string.format("% 9.03f")

Code: Select all

value = 123.005
com2_val = string.format("%07.03f", value)
print(com2_val )

value4 = 23.005
com2_val4 = string.format("%07.03f", value4)
print(com2_val4)

value2 = 123.005
com2_val2 = string.format("% 7.03f", value2)
print(com2_val2 )

value3 = 123.005
com2_val3 = string.format("% 9.03f", value2)
print(com2_val3 )

value5 = 23.005
com2_val5 = string.format("%09.03f", value5)
print(com2_val5)

Keith

[Ralph]

You can either align left or right, depending on where you put the spaces, I don't really see the problem there.

[Keith Baxter]

You can either align left or right, depending on where you put the spaces, I don't really see the problem there.

Hi,

The problem is understanding the formatting and how the max7219 (common one) will display the characters on the display.

I have beaten this dead horse so much that my whip is in bits and I cannot even make tasty pies out of what is left of the meat. it seams no-one is grasping what I am saying.

I will do a illustration tomorrow and post here.

Keith

[Ralph]

I know what you mean. But 99.99% is using that 8 segment MAX7219 thing, so there's not much to worry about.

[Keith Baxter]

Hi,

I am working on a instrument that will give insight as to what formatting has on a MAX7219 (common) display.

There will be a variety of format criteria and different string options.

More on this later. Just a teaser of what is to come. Not the difference between these two string.format() 's and what is displayed.

Keith

[CmteLucasGodoy]

I would like to thank you all for the replies. It really helped me a lot with my issue.

Best Regards,
Lucas Godoy