New project: GPS speedometer

[roswald]

Hi Mike; Sounds good so far. A "for sale" product to a Ferrari owner would have to fit the dash well. On a 360 Modena there's a good place to the right of the instrament cluster on the dash and just to the left and above the AC vent. My thought is it would have to be free standing, mountable without destroying anything and and be very attractive. All those together are hard to do. Induction shift lights would fit in well. I don't think you need an RPM readout. I plan to mount mine there. I am willing to remotely mount hardware and hard wire it in. I am also willing to make it a hard mount to the instrament bezel. I will incorperate shift lights from SPA design. I have to think more on a commercial unit. More later. Rich

[roswald]

Hi Mike; How is the progress on the GPS speedometer project? Rich

[Mike]

The speedometer works well. Here is the finished unit, which has been shipped to the customer. Built for a show car, this one displays speed, heading, GPS time, and has several show/demo modes. I have a kit of parts on the way for a second customer's unit, which will have a pulse output for a cruise control.

This is a large 0.8 inch non-multiplexed display: each digit has its own 74AC164 driver chip. It is bright enough for daylight use. The display brightness is continuously variable, and the decimal point goes away when you exceed 100 mph. With a minor firmware modification, it could have separate day and night brightness settings determined by a headlight input.

The device requires an ATMEGA88 or larger MCU, 2KBytes of program memory, and 100 - 200 ma of 12-volt power.

GPS speedometers in general read slightly low on turns and grades.

There is a video demonstration here, originally prepared for the customer:
http://www.opengpstracker.org/counter_demo.avi

Mike

[roswald]

Hi Mike; I am very impressed. My requirements are a bit modest. I do like the output for a cruise controle though and I would really like a larger display. I mentioned 1.5 inches and would like to get something close to that. Let me know how we proceed. Rich.

[Mike]

If you know where to get 1.5 inch digits, they will work. Do you have any?

Mike