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Does it also reset when not connected to the breadboard?
Make sure you’re not pulling over the 1A the AMS1117 can provide on the 3.3V rail and check to make sure the GPIOs are in the correct state to boot from flash
GPIO 0: HIGH
GPIO 2: HIGH
GPIO 15: LOW
It’s possible your NodeMCU (or clone) is poorly implemented as with chinesium jelly bean parts
I already bought 2 of these Orbit DC latching valves and I do like that they require no power to stay on.
The valve control is working fine now, I used a 2 channel relay board I had laying around as high side switches at the input and output of the boost converter, I can open the close the valve just fine with 20V and 2000uF, the valve sees about 18V.
Been shopping for MOSFETs, all logic level 3.3V TO-220 are expensive at $3-4 a pop, may end up using an N-channel AO3404/IRLML0030TRPbF or P-channel AO3407, pretty cheap on eBay ($3-4/100pcs) and relatively inexpensive even at Digikey at $5-6/10.
Since I have no experience with them, perhaps I’ll get the cheaper SOT23 to play with and if I fry them, no harm done 🙂
I’ve modded by ESP8266-Pro module from RobotDyn, lifted the flash chip’s PIN 3 and 7 and connected them to VCC, previously already flashed in DIO mode using ESP Flash Download tool.
Was able to use GPIO 9 and 10 to blink LEDs no problem, so 9 GPIOs free if I keep UART and I2C
I had some troubles with the inrush current of the 2000uF capacitor charging, was initially using a 2A boost converter module with a small SOT23 MT3608 IC but its built-in soft start wasn’t that great and the 5V USB power adapter goes into over current protection for a couple of secs until it’s charged up.
I then switched to a common XL6009 based QSKJ 4A boost converter and that one seems to far better (also have an ENable pin broken out if I have enough GPIOs to make use of it)
Also, if I don’t disconnect the boost converter’s output after charging up the cap and try to switch on the valve, it will keep sinking lots of current and you see the LEDs dim, had I have the ESP8266 connected for that test, no doubt it will reset.
So either have a separate PSU for the ESP8266 and a beefy 24V PSU just for the valves (of which I do have a spare one) or find some sort of way to limit the in-rush current as well as to disconnect the boost converter, using a MOSFET perhaps?
As for the L298, with its output paralleled, I was able to switch on/off the valve at 24V/2000uF during my test.
I’m surprised this topic hasn’t gotten any activities since last year but after reading through a couple thousand line changes of code between release 217 and current master of Ray’s code…it just occured to me that the ESP8266 merge (for OS3.0) is not the same code as pbecchi’s mod?
Would it be advisable to use OS3.0 code to run a custom ESP8266 or should I stick to pbecchi’s? I’m a web programmer and I can find my way through C.
I’m planning to just use 2-3 GPIOS per zone to drive a H-bridge for a DC latching valve (Orbit 91592)
Would a L298N provide enough current if I parallel the outputs for 4A max? Voltage drop is quite high however, specs list 4.9V @ 2A (!).
The RobotDyn L298 board have extra transistors and I can drive it with 2 GPIOS only, otherwise I do have a board with mofsets that can handle up to 7A (“XY-160D” red, some green, replaced the 1000uF cap with a 2200uF) but that board needs 3 GPIOS per H-bridge, so a total of 6 for 2 zones.
Btw, in order to use GPIO 9 and 10 (SD D2/D3, possibly different GPIO depending on the board), they must not be connected to the flash, so the pins will either have to be lifted or the trace cut off then pulled to VCC. And then flash with DIO mode using ESP Flash Download Tool, speed difference is minimal if you bump the SPI speed from 40 to 80Mhz
I guess I’ll modify my board once I receive the 4MB/64Mb flash chips, would 1MB/8Mb be sufficient however?
Perhaps not enough for OTA update? How big is the compiled code?
I may be able to get away with using GPIO 0, 2, 12, 13, 14, 15 (16 has no INT_PULLUP/OPEN_DRAIN since it has a builtin pulldown for the wake from sleep)
That leaves me with no GPIOs for buttons, I do have some expanders on order to play with.
It would be nice to get a rotary encoder working 🙂
My LCD is also a SH1106 1.3″ (SSD1306 is 0.96″) and it has a 132×64 framebuffer so the library has to take that into account and shift the image 2 pixels down.
- This reply was modified 1 year, 2 months ago by Daijoubu.