 | | Re: CdS cells
|
|
(...) It's certainly easiest to start out with a sensor that has a reasonable resistance range. However, if for whatever reason you have sensors that tend to be lower in resistance to the ideal, simply add your own resistor between the signal and (...) (27 years ago, 8-Aug-97, to lugnet.robotics.handyboard)
|
| |
| | Servo as drive motor
|
|
Hello, I have modified and connected 2 servo motors to the handy. The speed of one is much slower than the other. I swiched the motors around (first in Port (0),and (2) ) and then the reverse and the same motor is slower ... could I have fried the (...) (27 years ago, 8-Aug-97, to lugnet.robotics.handyboard)
|
| |
| | Re: CdS cells
|
|
David, I believe you will want to purchase ones that have a dark resistance more than say 20K. The sensor is part of a divider circuit that includes a 47K resistor. The sensed signal equals (sensor resistance)/(sensor +47K) multipled by 255. If your (...) (27 years ago, 8-Aug-97, to lugnet.robotics.handyboard)
|
| |
| | Obtaining a Handyboard in the UK
|
|
I just wanted to say that I ordered the HB from Hong Kong on Monday. I sended the money via my bank account and paid £12 for money delivered in 5 working days, or £17 for two. It containes: Kit A DB-9 or DB-25 (please select one of them, this (...) (27 years ago, 8-Aug-97, to lugnet.robotics.handyboard)
|
| |
| | Re: 3v motors
|
|
Yes Vs should stay at 5v, but if you read my original message the best thing is to use 9.6 volt motors!! Save yourself some trouble! jm (...) (27 years ago, 7-Aug-97, to lugnet.robotics.handyboard)
|
| |
| | Hong Kong
|
|
Hi, As an additional note about buying the HB from Hong Kong, be on the lookout for wire fees or bank draft fees. I have just purchased an HB and the price is indeed good, but I also had to pay a $12-$20 fee for getting the funds to Hong Kong. The (...) (27 years ago, 7-Aug-97, to lugnet.robotics.handyboard)
|
| |
| | Re: 3v motors
|
|
With the modification mentioned in the the FAQ, can you power 3V motor at 3V with external power? The FAQ mentions external 6-36V and L293D spec sheet says that the minimum Vs is Vss (which has a minimum 4.5V). The modification doesn't change Vss, (...) (27 years ago, 7-Aug-97, to lugnet.robotics.handyboard)
|
| |
| | Re: Obtaining the Handyboard in the UK
|
|
(...) I too talked to Customs and they are typically confused and confusing about import tariffs and such. I was told that the limit was £19 for what that is worth. I would probably just order the damn thing and see what happens. Tax probably won't (...) (27 years ago, 7-Aug-97, to lugnet.robotics.handyboard)
|
| |
| | Re: 3v motors
|
|
If you try to regualte the voltage to 3V You will still loose the extra power as in using a resistor. You lose it in the form of heat to be specific. Using a regulator will give you the 3V you need at continuous output. I'm not sure how voltage (...) (27 years ago, 7-Aug-97, to lugnet.robotics.handyboard)
|
| |
| | LCD
|
|
Does anyone know if the hb LCD is classed as reflective or transflective.If it is reflective is there a transflective counterpart(i.e. one that can be backlit)? Thank you, Joe Martin Email:joema@mpx.com.au (27 years ago, 7-Aug-97, to lugnet.robotics.handyboard)
|
| |
| | RE: 3V motors
|
|
Yes, it is true that altering the duty cycle does not alter the voltage. What it does do it alter the amount of current to the motor. The problem with these motors is that they draw too much current, more than the HB can readily provide them. By (...) (27 years ago, 6-Aug-97, to lugnet.robotics.handyboard)
|
| |
| | Re: 3V motors
|
|
Also, something to keep in mind regarding the motor drivers is that "lowering the power" doesn't change the drive voltage. I assume (ok, here's a chink in the argument, if this is wrong, I hope Fred or someone will correct me) that the handyboard (...) (27 years ago, 6-Aug-97, to lugnet.robotics.handyboard)
|
| |
| | Interrupts in Interactive C
|
|
There a way from assign to a interrupt some function wrote in interactive C? How I can put the vector (for the SPI for example $FFD8) pointing to my source???? Thanks in advance. German Pablo Gentile Analista de Sistemas ggentile@cvtci.com.ar (27 years ago, 6-Aug-97, to lugnet.robotics.handyboard)
|
| |
| | Re: 3V motors
|
|
I too had a problem with 3 volt motors. The issue is the height of the PWM output. If you drive your motor function at 50%, then 50% of 9.6V is still much higher than the 3 VDC for full speed. One way to get some resolution is to modify the supply (...) (27 years ago, 6-Aug-97, to lugnet.robotics.handyboard)
|
| |
| | Motors
|
|
Hi. I am running two 3.3V motors with the handy board. Sometimes The motors would just stop running. The leds that indicates the motors are running are still lit. Also the two chips next the motor output gets very hot. The number on the chip is (...) (27 years ago, 6-Aug-97, to lugnet.robotics.handyboard)
|
| |
| | MAgentic card readers again...
|
|
Anyone can help me about the way to connect a magnetc card reader to the handy? I use the idea from david negro , that use the SPI port, but i don't can make work the code... Can anyone tell me uf exists other source of that info ont the web?? (...) (27 years ago, 6-Aug-97, to lugnet.robotics.handyboard)
|
| |
| | Re: IR output on HB
|
|
No, don't use a transistor! The HB's IR out already has one. But the parallel-with-a-sepa...r-for-each method is correct. -Fred In your message you said: (...) (27 years ago, 5-Aug-97, to lugnet.robotics.handyboard)
|
| |
| | Re: IR output on HB
|
|
Run them in parallel, use a transistor. Like so: +5v | +---+---+---+---+---+ | | | | | | \ \ \ \ \ \ / R / R / R / R / R / R \ 1 \ 2 \ 3 \ 4 \ 5 \ 6 / / / / / / -- -- -- -- -- -- \/ \/ \/ \/ \/ \/ -- -- -- -- -- -- HB + | | | | | | \ | | | | | | / (...) (27 years ago, 5-Aug-97, to lugnet.robotics.handyboard)
|
| |
| | Re: CdS cells
|
|
[David.J.Dostal@lawrence.edu] spake unto the ether: (...) I just ordered some from Mouser, the smaller of the two physical sizes they have, 3K to 100K I believe are the light/dark resistances. These give analog(PORT) values of about 10 in ordinary (...) (27 years ago, 5-Aug-97, to lugnet.robotics.handyboard)
|
| |
| | CdS cells
|
|
hi everyone, I am looking to purchase a batch of CdS photo cells but I think that I need more information before I order. The catalogs (Digi-Key, Mouser, etc.) list several different photocells (different resistances, power dissipation, etc.) and I (...) (27 years ago, 5-Aug-97, to lugnet.robotics.handyboard)
|
