Fiz WROTE:HELoooooo Allen~~~~As always and expected, u sooo awesome!! Thanks for replying and your enlightenment also the information..Its so nice to know your opinion, uhmm..what actually i'm trying to do here is, a sensor(to detect the speed,btw idk what term of method to get the speed maybe rpm or other easier method) attached to the bicycle spinning part;shaft? or at the brake gripper(by remove the gripper(rubber) and replace with the sensor and interface with I.C to interpret it(frequency to voltage I.c probably; LM2917? or... i hunger your opinion actually..) and connect to the display(7 segment;maybe used up to 2 or 3 segments). But,i prefer to take toy cars as the modal instead of bicycle..Anyways, you are my savior..for real~~Thanks again.
Thank you for your kind compliments but I know I am not that good as you thought
My bike computer is based on the article here:
http://www.piclist.com/techref/piclist/ ... /index.htmOn chapter 10, the author mentioned about the sensor using hall effect detector which is different from mine. In order to mount the sensor, you can refer to the diagram here:
http://www.ebay.com.my/itm/LCD-Bicycle- ... 27bbe19306Scroll further down and you will find the diagram how to mount the magnetic sensor on the front wheel.
As for the use of LM2917, few years ago, my friend has designed a RPM meter based on this chip but the result was not so good. In his design, he used an anlogue meter to measure the voltage converted from frequency. The RPM that he measured was very low, like 100 to 600 RPM. When the RPM is low it took long time to update the meter. Later his switched his design using PIC and that worked successfully. He now has a version using 16F877A and was able to measure RPM on both right and left engines. It even took care of the reverse direction by displaying the word "ASTERN" underneath the rpm number in the LCD display. He told me the program was written in PIC Basic Pro.
cheers
Allen