ESP-DSC Works Not Well!

So yesterday I was all happy that I got my prototype ESP-DSC working. This ended up being short lived as I realized this morning that while it does technically work, the ESP8266 can’t keep up with two medium resolution (2,500 CPR) encoders.

Ironically, I found out that the code was too slow when I started to optimize the code and I realized that the code I has was very very conservative. My original optimization was to speed it up, but maintain that conservative ethos. I figured while I was editing the code, I might as well also add a test to see if the ESP-12F was dropping interrupts… Continue reading


New low cost digital setting circles: ESP-DSC

So a few years ago, I announced TeensyDSC, project that brings telescope digital setting circles to the iPad and Android devices using WiFi. I’ve been using my TeensyDSC successfully with my telescope and SkySafari on an iPad for a few years, but one thing always bothered me about it: the “COGS” (cost of goods sold) of the TeensyDSC was really expensive: nearly $100. A lot of that cost was in two parts: the Teensy 3.1 ($20) and RN-XV WiFi module ($35).
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SV650 ECU Decoder v4.6 Design Finished

So I just ordered a few new boards from OshPark:



This was a major update which fixes all know bugs (many which are severe) and improves the protection of the circuit.

  • Switch to Murata 5V switching regulator.
  • LM7805 was overheating with heavy use of LED display in latest code
  • Add power MOSFET for reverse polarity protection
  • Add TVS diode for power/spike protection
  • Fix fuel/very low fuel indicator for 03-04 and 05+
  • Move EFI light off of pin 11 to allow interrupts to work
  • Move Mode switch to an interrupt pin
  • Add ground plane & clean up traces
  • Further improve battery voltage monitoring
  • Capacitors are now SMD too

v4.1 board design finished!

I’m happy to announce I’ve finished with the latest design of the SV650 ECU Decoder which has a number of improvements:

  • Add button for switching the display modes
  • Add support for detecting “very low fuel” on 2005-07 models
  • Improve battery voltage measurement circuit
  • Small tweaks to the layout and silkscreen

The board design has been sent to OSH Park for fabrication and hopefully I’ll get them in about 2 weeks.

Here’s a rendering of the new PCB design:

v4.1 Top

v4.1 Back

Update: So some testing of this board is showing some problems, including a possible problem which causes the Teensy board to be damaged, so I’m currently suggesting people not use it!


SV650 ECU Decoder Part 4: Third time is the charm?

Part 1 is here.
Part 2 is here.
Part 3 is here.

So my v2.0 boards were a complete dud.  Turns out some how I messed up the design and ended up wiring up the connector to the wiring harness backwards so nothing works.  Wasn’t a complete disaster- I was going to have to do another revision of the board either way, but it does slow things down. Continue reading