Guru
Joined: 21/06/2018
Location: AustraliaPosts: 1156
| Posted: 01:11pm 11 Jul 2022 |
I have rebuilt a new power PCB but before I hooked it up to the Nano I wanted to run some testing as I was sure there were some issues with D5, the enable for the outputs.
The transformer is ~31.2V at ~235V out.
It was intended to still provide 235V at 44V which is the low voltage cut out.
If I did it again I would probably go for ~33V and be happy with a bit of droop below 46V as it approaches 44V.
The following CRO pictures tell an interesting story (apart from my lousy/noisy ground).
The Purple trace is the D8 input that tells the Nano "please start"
The Yellow trace is D5 & its supposed to go High at ramp up start after D8 has been told "go".
The Blue trace is just the 5V coming to life after turn on, for relativity.
This is the 1000 step code as received
This is the 1000 step code with SST = 100
Note D5 went high for 1 second immediately the 5V rail went active & before D8 was told to "go"
This is the 1000 step code with SST = 200
Note D5 went high after Power up and just stayed high
I did say yesterday that it behaved as though D5 was being enabled before the start command.
Poida this is why we pay you the big bucks, to solve all the weird problems
Its probably caused by a missing comma or = sign or something simple but the results are a bit bizzare.
Thanks for your comments on what I did and agreeing it should have had the effect I wanted - it looked reasonable to me but I am software challenged and software is easily broken.....
The really sad part is that the middle picture with the premature enablation (is that a word ?) is the one that doesn't grunt and starts real nice
Edited 2022-07-12 00:31 by wiseguy