Thanks. By the way, there is a messed up link there. I do have one related question. Is it possible to set the actual frequency? Or is sort of you get what...
... I learned that the SPCR in atmega is greater than 32 and sbi usually works for i/o less than 32 so I tried to replace the sbi instructions in fpu_reset(): ...
Hi Steve, I fixed the app note link. Thanks. The V3.1 default clock speed is 29.48 MHz. The chip will try to run at the selected clock speed. It can be changed...
Thanks. It's getting clearer but I'm not out of the woods yet. First, I find the wording confusing. In the AN it says "maximum clock frequency is." and in...
The clock frequency used depends on a configuration byte stored in Flash memory. The setting of this byte determines the clock frequency. That's what the $C...
Ok, so if the uMFPU is not changed from its default factory settings, and I power it from 3.0 V, then it will "fail", it will default down to 1.8452 MHz and I...
I am using the Print_Float instruction to print a calculated float value. This is after I have called parseNEMA command as written in app #38. The correct...
Bernard Drew
bernardrew@...
Apr 30, 2009 3:44 am
273
The FTOA instruction used by the Print_Float routine stores the floating point string at the insertion point of the string buffer. The parseNMEA function uses...
Thank you. I am slowly getting up to speed on this very useful chip. Bernard Sent from my iPhone Cell: (678) 357-3869 On Apr 30, 2009, at 9:28 AM, "Cam...
Bernard Drew
bernardrew@...
Apr 30, 2009 3:17 pm
275
Good day. I am attempting to integrate 3 axial rates into a proper representation of attitude WRT to the original (start up) attitude. I have the sensors...
Hi, It is not quite clear to me wether OUT0 and OUT1 are normal TTL outputs or open collector outputs. There is mention of connecting a LED via 1k resistor to...
Hi Peter, OUT1 and OUT2 are normal TTL outputs, not open collector. They can each source/sink a maximum of 25 mA. A LED connected to OUT1 as a busy indicator...
Thanks Cam for the quick reply. Please see file umFPU OC.pdf that I uploaded to the files section. I added 2 NPN transistors to turn OUT0 and OUT1 into OC. ...
Hi Peter, OUT0 and OUT1 are hi-Z at reset. The SERIN/debug mode check at reset can be disabled by setting bit 7 of parameter byte 2 (see datasheet-pg16). If...
Hi Cam, Here is my order of events to program the umFPU. CS is pulled high via 10k resistor and USB2SER is connected. So CS=1 and SERIN=1, thus debugmode is...
Hi Peter, The basic procedure sounds good, but you also need to set bit 7 of mode byte 2. Without setting that bit, one case you described previously ... would...
Hi Bryan, Problem 1: ATOF fails on 23.860929422222222. You've identified a problem with the ATOF instruction when handling numeric strings with more than 9...
Thanks, I've got most of this figured out now. I don't need that much precision. I still need a good amount of it though. Here is exactly what I'm trying to...
Hi Bryan, ... The ATOF limitation I mentioned in the previous post was 9 significant digits, not 9 digits. The value 60000000 has only one significant digit,...
Thanks, I just have one more question about this example: 1431655765 = (60000000*4294967296)/180000000 If I did (60000000*4294967296) and put the result in a...
Hi Bryan, ... Either will work fine. The reason this works is that 4294967296 is 2^32. Although it looks like it has too many significant digits, since its a...
Hi, I tried to do this as you described, But it is not working for me. Here I have it like this: SETUP CONSTANTS X R0 = 4.294967e+9 this is the constant 2^32 A...
Hi Bryan, You only show parts of your code, so it's a little difficult to know exactly what's happening. I've tested the code I send you earlier, so I think...
Hi, wondering if my Chip is faulty in some way as I can't even do a simple multiply of a float by an longint. For instance if I want to multiply 1.23 x nn I...
Hi Bryan, You can't do math operations on registers with different data types. If you want to multiply a float by a long, you need to first convert the long to...
Writing to let you know I am greatful for your help and patience with me. Learning to intergrate code and electronic components together so they can work...
Hi Bryan, Glad to hear you've got things working. ... uM-FPU V3 ID Release 2.0 beta6 does have a string display window, but the only way to use it properly is...
Having problems with message search?
Fill out this form to ensure your group is one of the first to be migrated to the new message search system.
