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SuB-ZeRo
- 21st June 2005, 20:00
Yes.If PBP can handle LCD with basic commands.Why 7 segment not?
:)

Melanie
- 21st June 2005, 20:57
Most LCD's have a high-level embedded controller, and most follow the same origianal Hitachi pattern. PBP provides for this nicely.

7 segment displays are basically a bunch of lights. There's a hundred different ways you can connect them up. You can have common anode, or common cathode, with one limiting Resistor, or with seven. Driven or undriven. Time multiplexed or constant. etc etc.

It is assumed by manufacturers that most people can connect up a bunch of LED's and make them work in one way or another (LED example at the start of the PBP manual just expanded up seven times is a good start) - folks that can't (or don't want to sit down with a protoboard and play) should really consider a different hobby.

Luciano
- 21st June 2005, 22:35
See URL:
http://picbasic.com/resources/articles/ledart.htm

LED displays are difficult to read when viewed in sunlight.

Luciano

crematory
- 29th July 2005, 17:04
Hello

There is no need for the support of SEVEN SEGMENT DISPLAYS any way, as they always need some kind of multiplexing/refreshing issues that causes annoyance to the PIC programmer, the simplesy way is to use TMR0 overflow, which will then have to be polled, or used in interrupt.

So why bother your self my friend, if I want to use four seven segment displays then this will cost me 9$, while when I go for an LCD I will pay 14$, also think about it as more cost effective option, as you can view text also :)

Have a nice day

mister_e
- 29th July 2005, 17:57
I agree with you, but sometimes some customer need bigger display, see simple bigger number. So you have 3 choice IMHO

Care about everything with timer interrupt or else method...
Use a dedicated PIC who will do only that and receive data via USART or SERIN blah blah (sefull when you still have those dusty 16C54 and ooooh HOW many others)
Use dedicated ICs like those from national who work with a simple I2C bus

crematory
- 29th July 2005, 18:20
Hello mister_e

I think you made your point loud and clear, yes, some times we need to see bigger numbers.

As you said, there are other ways to do this, for example we can use ICL7218 and ICL7228 which is a nice idea to use also, kicking out the PIC16F84A capabilities, instead of going to a larger I/O PIC, etc...

Regards

Melanie
- 30th July 2005, 17:39
> So why bother... four seven segment displays then this will cost me 9$, while when I go for an LCD I will pay 14$...

I think the disparity is much greater... a two digit seven segment display in bulk costs about 30 cents (US) whilst the cheapest LCD Display (Hitachi compatible) is just under $1.25. Despite all the drawbacks, the seven segment display remains the cheapest solution for many applications. My original comments at the start of this thread still stand... if you can connect up and program an LED, you can connect up and program a device with seven of them.