Re: The VeeCU
Posted: Mon May 17, 2021 2:36 pm
HI Guys,
Back from the park and working on injection pulses.
Here is a shot of three of the injector pulses. One pulse has zero delay and 10 micro second duration. The second has 10 micro seconds of delay and 20 micro seconds of duration. The third has 30 micro seconds of delay and 30 micro seconds of duration. The forth was too hard to get to :-)
The delay and duration are controllable in 10 micro second increments up to (delay + duration) = 65535. Setting the timer to 10 micro second increments allows 0.65535 seconds as the maximum pulse width. I can't imagine every needing more than that. And, 10 micro second resolution on injector pulse width seems more than adequate. It makes for simple code so I'm calling that good enough.
It's time for what new grads call re-factoring. It's what we used to call clean up. I'll start a new project in the development environment and bring the code over piece by piece improving/simplifying where ever possible.
Looking to the future, I've implemented the 3-D lookup routine for typical VE lookup. Not sure that is the way I'll go but I'm ready if that's what I decide. It's interesting to see all the hoops folks jump through trying to get a good start (Ref.https://www.hptuners.com/help/vcm_editor_parameters_gm_eng_fuel_general.htm). We'll see how that goes :-)
It's time to start considering signal conditioning. Can I really replace my ignition coils with optical couplers?? Hum....
EDIT: So, I couldn't resist. I went to the shop and replaced one of the ignition coils with a 10K just for a test. When the DYNA-S fired the low end of the resistor went to 0.5 volts and then back all the way to bus voltage while "charging". The DYNA-S hung in all the way to below 5 Volts at which point it just turned on (0.4 volts). So, looks like appropriately sized resistors and opto-couplers is a viable option for acquiring the secondary ignition pulse.
Forever Forward,
Wes
Back from the park and working on injection pulses.
Here is a shot of three of the injector pulses. One pulse has zero delay and 10 micro second duration. The second has 10 micro seconds of delay and 20 micro seconds of duration. The third has 30 micro seconds of delay and 30 micro seconds of duration. The forth was too hard to get to :-)
The delay and duration are controllable in 10 micro second increments up to (delay + duration) = 65535. Setting the timer to 10 micro second increments allows 0.65535 seconds as the maximum pulse width. I can't imagine every needing more than that. And, 10 micro second resolution on injector pulse width seems more than adequate. It makes for simple code so I'm calling that good enough.
It's time for what new grads call re-factoring. It's what we used to call clean up. I'll start a new project in the development environment and bring the code over piece by piece improving/simplifying where ever possible.
Looking to the future, I've implemented the 3-D lookup routine for typical VE lookup. Not sure that is the way I'll go but I'm ready if that's what I decide. It's interesting to see all the hoops folks jump through trying to get a good start (Ref.https://www.hptuners.com/help/vcm_editor_parameters_gm_eng_fuel_general.htm). We'll see how that goes :-)
It's time to start considering signal conditioning. Can I really replace my ignition coils with optical couplers?? Hum....
EDIT: So, I couldn't resist. I went to the shop and replaced one of the ignition coils with a 10K just for a test. When the DYNA-S fired the low end of the resistor went to 0.5 volts and then back all the way to bus voltage while "charging". The DYNA-S hung in all the way to below 5 Volts at which point it just turned on (0.4 volts). So, looks like appropriately sized resistors and opto-couplers is a viable option for acquiring the secondary ignition pulse.
Forever Forward,
Wes