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In the Handyboard manual it says when charging in trickle mode you should turn the Handyboard off, however when I do try and turn the Handyboard off the charge light on the serial/charger board goes off? Is the board still being charged or is there (...) (25 years ago, 16-Nov-99, to lugnet.robotics.handyboard)
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| | Re: evaluate inverse cosine, sine in IC
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(...) The most efficient way to do it is to use Taylor Series approximations of the functions. Decide how much precision you need, and then write functions that evaluate the first few terms in the appropriate series. Usually, a series will converge (...) (25 years ago, 16-Nov-99, to lugnet.robotics.handyboard)
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| | evaluate inverse cosine, sine in IC
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Hi, is there a way to evaluate inverse cosine and sine using IC? Thx (25 years ago, 15-Nov-99, to lugnet.robotics.handyboard)
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| | Re: Video Transmitters
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(...) I't not that cheap, but if you want small size and low power consumption check out this 900 Mhz transmitter/receiver pair from supercircuits: (2 URLs) here's a very small camera with transmitter built in: (URL) if you want to receive on a (...) (25 years ago, 15-Nov-99, to lugnet.robotics.handyboard)
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| | Re: Video Transmitters from JDR
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[glashan] spake unto the ether: (...) From the fancy TV receiver you describe, I'd say you wouldn't have to do anything but select NTSC mode. The kit is supposed to transmit over the range of VHF channels 3-7, but my specific kit only does 3-5 (why (...) (25 years ago, 14-Nov-99, to lugnet.robotics.handyboard)
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| | Re: Video Transmitters
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NetMarket (www.netmarket.com) carries a transmit/receive pair made by Recoton. It's intended to transmit audio/video around the house. Ours includes a gizmo to extend your remote control capabilities, and it cost about $120. Just the (...) (25 years ago, 14-Nov-99, to lugnet.robotics.handyboard)
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| | Re: mixing variable types in IC
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[Ben Davis] spake unto the ether: (...) Hmm, I think you want c = ((float)(x))/((float)(y)); Otherwise, the division will be done first as integers, giving an integer quotient, which you're then turning into a float. *Rich* (25 years ago, 14-Nov-99, to lugnet.robotics.handyboard)
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| | mixing variable types in IC
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Hi John- You can convert quantities from one data type to another (it's called "casting", I believe). The following computes the quantity x/y, then converts it to a float: ---...--- int x, y; float c; float divide ( int x, int y) { c = (float) (...) (25 years ago, 14-Nov-99, to lugnet.robotics.handyboard)
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| | mixing variable types in IC
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Now that I got past my nested function problem I have discovered that IC does not like mixing variable types. For instance, this results in an error: int x, y; float c; float divide ( int x, int y) { c = (x/y); return c; } IC will not let me (...) (25 years ago, 14-Nov-99, to lugnet.robotics.handyboard)
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| | Re: Video Transmitters
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[glashan] spake unto the ether: (...) JDR Microdevices ((URL) sells a $25 short-range VHF TV transmitter kit. It's all analog, so there is some drift with warmup and it needs a very stable power supply, but otherwise it works great. The observer (...) (25 years ago, 14-Nov-99, to lugnet.robotics.handyboard)
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| | Video Transmitters
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Hi all I wonder if anyone out there can help me with this: Im looking for a cheap video transmitter or circuit diagram. Ive got a small board camera on my bot and I need to find some way of sending the video to my TV. I dont want to go out and spend (...) (25 years ago, 14-Nov-99, to lugnet.robotics.handyboard)
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| | Re: IC trouble - function definition - understand now, Thanks
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Sorry, Forgot to enclose the code. what is wrong here? long time; void phony() { while (digital(2) == 1) { time = mseconds(); printf("%d\n", mseconds()); } if (mseconds () >1413 ) fd(1); else bk(1); } void start() { phony(); } void main() { while(1) (...) (25 years ago, 13-Nov-99, to lugnet.robotics.handyboard)
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| | Re: IC trouble - function definition - understand now, Thanks
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John, Have been following your problems with function definition. what is wrong with this code? It will print the mseconds but the if statement does not work. Thanks Terry -----Original Message----- From: John Bachman <bachman@anatek.mv.com> To: (...) (25 years ago, 13-Nov-99, to lugnet.robotics.handyboard)
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| | Re: IC trouble - function definition - understand now, Thanks
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Rich got it. Nested functions was the problem. I don't recall seeing that discussed in the IC manual and I think it is OK in C. Nonetheless, thanks to all for helping this hapless programmer. John (...) (25 years ago, 13-Nov-99, to lugnet.robotics.handyboard)
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| | Re: IC trouble - function definition
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(...) whoa! Local function definitions. Even GCC doesn't grok that. Try extracting the function definition phony() from start() like so: long time; void phony() { while (digital(2) == 1) { time = mseconds(); } } void start() { phony(); } -d (...) (25 years ago, 13-Nov-99, to lugnet.robotics.handyboard)
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| | Re: IC trouble - function definition
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[John Bachman] spake unto the ether: (...) You have the definition of phony() nested inside the definition of start(). I don't know what ANSI C and/or C++ let you do, but this is invalid IC. You need something like: long time; void start() { (...) (25 years ago, 13-Nov-99, to lugnet.robotics.handyboard)
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| | Re: IC trouble - function definition
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Thanks for all the helpful device but the darned thing still does not work. I have created a simplified program to try to figure out what I am doing wrong. Here it is: /* A simplified program to figure out what is wrong */ long time; void start() { (...) (25 years ago, 13-Nov-99, to lugnet.robotics.handyboard)
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| | Re: IC trouble - function definition
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John: If your function does not need a parameter passed to it just do: void detect_time2() { /* code here */ } just like int main() { /* code here */ } Bart. ___...___ Reply Separator ___...___ Subject: IC trouble - function definition Author: (...) (25 years ago, 12-Nov-99, to lugnet.robotics.handyboard)
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| | Re: IC trouble - function definition
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John: Try it like this----- void detect_time_2() {same code here;} IC is a lot like ANSI C, but there are some differences. Good luck, Gary Livick (...) (25 years ago, 12-Nov-99, to lugnet.robotics.handyboard)
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| | IC trouble - function definition
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I am having trouble with function definitions. Can someone tell me what is wrong with this: void detect_time_2 (void) { code here;} I get a syntax error on the definition line and cannot figure out why. TIA John (25 years ago, 12-Nov-99, to lugnet.robotics.handyboard)
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