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hi I'm trying to do a program that has to show a result with only two decimals (from a mathematical operation). At the moment I'm using CSng to output decimals but this method shows too many. Any hint on how to get the uC to show up (print on monitor) only 2 decimals? Thanks!

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> ... Any hint on how to get the uC to show up (print on monitor) only 2 decimals? I can suggest two methods: 1- Function Fmt(2.345, 2) yields string "2.34", and 2- You can construct the equivilent with Mid, cStr and cInt. Tom Tom Becker --... ...-- www.RighTime.com The RighTime Clock Company, Inc., Cape Coral, Florida USA +1239 540 5700

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--- In , "Tom Becker" <gtbecker@r...> wrote: > [...] > 1- Function Fmt(2.345, 2) yields string "2.34", and Note, however, that Fmt() doesn't round; it simply truncates. Fmt (2.346, 2) also yields the string "2.34". I have written some formatting routines that do round properly. However, they generate characters into a byte array which you would then have to either display individually or convert to a string. Also, the routines can optionally justify the resulting digit sequence within a fixed number of characters (centered, flush left or flush right). This is handy for emitting to an LCD. You can find the routines at the link below and may use them for non- commercial applications. http://www.kinzers.com/don/BX24/Routines/Format.bas

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> Note, however, that Fmt() doesn't round; it simply truncates. No, I chose 2.345 deliberately to show that the result is "2.35", Don. The function rounds up, I didn't; my error. Tom Tom Becker --... ...-- www.RighTime.com The RighTime Clock Company, Inc., Cape Coral, Florida USA +1239 540 5700

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--- In , "Tom Becker" <gtbecker@r...> wrote: > I chose 2.345 deliberately to show that the result is "2.35". > The function rounds up. You're right, it is rounding up. I'm more accustomed to seeing "statistical rounding" where 2.345 would be rounded to 2.34 but 2.315 would be rounded to 2.32.

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Thanks! Ok, what I'm trying to do is to calculate a value and store it in A, then when I print this value I want it with only 2 decimals. I tryed your example but I don't seem to get it, sorry I'm a bit new to this. --- In , "Tom Becker" <gtbecker@r...> wrote: > > ... Any hint on how to get the uC to show up (print on monitor) only 2 > decimals? > > I can suggest two methods: > > 1- Function Fmt(2.345, 2) yields string "2.34", and > 2- You can construct the equivilent with Mid, cStr and cInt. > Tom > > Tom Becker > --... ...-- > GTBecker@R... www.RighTime.com > The RighTime Clock Company, Inc., Cape Coral, Florida USA > +1239 540 5700

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> ... calculate a value and store it in A, then when I print this value I want it with only 2 decimals. OK, let's print the value of the squareroot of five, to two decimal places. Sub Main() dim sA as single sA = 5.0 ^ 0.5 Degug.Print Fmt(sA, 2) End Sub You should see 2.24, although the value is ~2.23607. Tom Tom Becker --... ...-- www.RighTime.com The RighTime Clock Company, Inc., Cape Coral, Florida USA +1239 540 5700

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--- In , "Ed" <esteyezz@y...> wrote: > I tryed your example but I don't seem to get it... Insufficient data. Show us exactly what you tried and and describe what you observed. Someone may be able to spot what change is needed.

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Thanks a lot! That is what I wanted, it is working now!! The program is reading the output of an accelerometer (ADXL202) and I wanted it to display only 3 decimal points for every measurement. I have the accelerometer set to 1000 samples per second but I'm only getting about 20 from the uC, any idea how fast can the uC take samples?

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Ooopppss, I forgot about the serial port while monitoring the unit. Without it i get about 200, any good? Can it go faster? Thanks a lot for the help

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> ... Can it go faster? This is a classic issue of throughput, the combined limitations by the source rate, the input rate, the processing rate and the output rate. It seems to me that you can control all four. So, to see how fast you can input data alone, do little processing and little output. For example, just measure input rate, maybe for 10 seconds, and display it once, or loop, counting for a second and display it once per loop. You can answer your question. Tom Tom Becker --... ...-- www.RighTime.com The RighTime Clock Company, Inc., Cape Coral, Florida USA +1239 540 5700

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It is what I was thinking. I'm now simplifying my code to see if I can gain a little bit of speed. I'm interested on measuring frequencies below 20Hz but i wouldn't mind to have a bandwidth [BW] of 0-100Hz. At the momento I'm just looking for specific values coming from the accelerometer but i was thinking this: Could it be possible to to sample a signal for 10 seconds and then do an FFT analysis and output the values Freq. vs Amplitud? Do you think the uC is powerful enought for this? The other option I was thinking is to do a similar thing, sample 10seconds and send it to the computer, then here the PC makes the FFT calculations and refreshes it every 10 seconds (or 5 or any time). My problem is that I was thinking to do this using a free FFT analyser for audio but of course, usually audio cards don't go below 20Hz so I have to find my own ways. For the kind of BW I'm interested, it shoudn't be a lot of work, shouldn't be? Thanks a lot for your support!! Ed --- In , "Tom Becker" <gtbecker@r...> wrote: > > ... Can it go faster? > > This is a classic issue of throughput, the combined limitations by the > source rate, the input rate, the processing rate and the output rate. > > It seems to me that you can control all four. So, to see how fast you > can input data alone, do little processing and little output. For > example, just measure input rate, maybe for 10 seconds, and display it > once, or loop, counting for a second and display it once per loop. > > You can answer your question. > Tom > > Tom Becker > --... ...-- > GTBecker@R... www.RighTime.com > The RighTime Clock Company, Inc., Cape Coral, Florida USA > +1239 540 5700

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> ... sample a signal for 10 seconds and then do an FFT... I doubt you would have sufficient RAM with the BX-24, which has about 400 bytes to work with. A BX-01 with additional RAM, though, could do an FFT. Otherwise, your last idea of doing the FFT on a desktop might be best, I think. It would not be difficult to collect your accelerometer data with a BX-24 and send it to a desktop machine in real time. With that data your desktop app could build a .wav file, which you could then examine in detail with any of many audio editors like CoolEdit. Tom Tom Becker --... ...-- www.RighTime.com The RighTime Clock Company, Inc., Cape Coral, Florida USA +1239 540 5700

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Note the documented restriction in the range of the number... From BASIC EXPRESS COMPILER REVISION HISTORY V2.01 "[...] Fmt is a low-RAM version of VB's Format function, and converts floating point numbers to strings with a user-specified number of digits aft of the decimal point. The new function handles numbers in range -999 to +999, and 0 to 3 digits aft of the decimal point."

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In addition to Don's functions shown earlier in the thread, you can roll your own display format function, of course. Here's one example that displays a signed value, -10.0000 < sIndicatedError < +10.0000, to three decimal places, rounded high: Dim strX as string, strZ as string If 0.0>sIndicatedError Then strX=" -" 'show sign Else strX=" +" End If strZ=cStr(cLng(Fix(Abs(sIndicatedError * 1000.0 + 0.5) + 10000.0))) strX=strX & Mid(strZ, 2, 1) & "." & mid(strZ, 3, 3) Call PutStr_1(strX) ' -x.xxx Tom Tom Becker --... ...-- www.RighTime.com The RighTime Clock Company, Inc., Cape Coral, Florida USA +1239 540 5700

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