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Messages posted by: empeka
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Wiring was ok, so i turned on putty and opened a serial connection via the FTDI. The Terminal show repeatly "NON GENUINE DEVICE DETECTED".

How to solve this Problem?

either use geniune ftdi chip, or don't use crippled driver - version should be fine (not sure if it'll work with windows 10 though)
more info here: http://hackaday.com/2014/10/24/ftdi-screws-up-backs-down/
I definitely will need some battery for this, and connect it directly to ??? instead Vin

mcp1703 quiescent current is ~2uA, so i wouldn't bother with powering board directly
now I have 43-44uA in sleep mode.

that's possible acording to spansion flash's datasheet.
see table here

Try without flash chip soldered, if you have proper tools to remove it.

also I have 7 termosensors DS18B20 in my system. And if these sensors connected - power drain increases to 0.2mA in sleep mode.

They don't have to be powered all the time. Turn them on only when you need them.
Assuming that max operating current of DS18B20 is 1.5mA, you should be completely safe feeding them from digital IO port.
(recommended max current of digital IO pin of atmega328p is 20mA)

Or (more properly) power your sensors from separate circuit turned on with mosfet.
radio module and spi flash have to be put to sleep before MCU
comment out lines 32 and 37. Repeat measurements.
Skim through this thread

1: Put everything to sleep. Including flash and radio module.
2: if you're using RFM69 desolder 10K D2 pullup resistor.
3: if your power source is stable, you could try bypassing voltage regulator
4: if you still need more savings, you could replace flash mem with more energy efficient (W25X40CL for example)
cambazz wrote:Hello,

The anarduino module with rfm98w is undocumented at this point. For example the DIO0 and DIO5 on the RFM98W module, are connected to pins 4 and 2
which i had to figure out by measuring.

There are many pins on the RFM98 module. How can i figure out which pins it is connected to?

D2 RFM interrupt
D3 rtc interrupt
D5 flash mem SS
D11-D13 SPI

SDA & SCL (A4, A5) are used with flash mem.
There are also pull-ups on interrput and SDA pins.
There are no other connections as far as i know. (including pin 4 you mentioned)
few more random thoughts:
- you can downclock atmega328p to 8MHz with fuses (thus reducing power consumption and minimal voltage required to run stable)
- you could design switchable booster circuit:
1.8V is enough to run this MCU at 8MHz, so you could feed it directly from near-end-of-life battery (especially if it will be in sleep state most of the time [I assume])
MCU could swith such booster to boost voltage up to 3V3 when it's really required (using sensors, radio transmissions)
- consider using 3.6V batteries
miniwireless has mcp1703 voltage regulator, so as long as you powering circuit through VCC pin you'll be fine with anything from 2.7 to 16V.

That's the safe way.
But if you're trying to squeeze every µA, you may try to remove MCP1703 completely and power your board directly throug 3V3 pin.
as long as input voltage stays ~3V you should be fine. Running atmega outside it's specs is possible, but when the voltage drops below certain threshold (that varies greatly depending on many factors, including temperature) you'll start experiencing undebuggable issues (memory corruption, freezes etc).
And that's where BOD kicks in. Atmega328p has (configurable) brown out detection that shuts down MCU when input voltage is below 4.3, 2.7 or 1.8V.
I'm not sure which value miniwireless boards are shipped with.

Also, read this: http://forum.anarduino.com/posts/list/0/39.page
I'm pretty sure your flash's manufacturer id is not 0.
Fix this and you should be fine
Yeah, low power series is what interests me most.
unless 1284 can achieve <4uA in sleep mode
stevech wrote:What does Dr. Ohm say to Dr. Ampere about 3.3 / 10,000?

Right, 330uA
And the remaining 16 is drained by SPI Flash in standby mode (which is nice, as if I identified chip correctly, it drains 70uA typically). Deep Power Down
The Deep Power Down (DPD) function is not supported in FL-S family devices.

So... anyone knows some low power replacement?

Answering my own question:
W25X40CL supports Deep Power Down with <1uA current.
I'ts a lot smaller than Spansion (4Mbit vs 128Mbit), but still enough for wireless flashing.
W25Q128FVSG is a bit pricey, but has 128Mbit with 1uA (typ.) power-down current
Ok, so the cause is 10K pullup resistor between D2 and 3V3. (located near RX/A7 pins on the board).
Power consumption fell to ~16uA after desoldering it. As far as i know it's not required when using RFM69 module.

empeka wrote:Anyway, i'll try with just writeReg(1, 0);

No difference. Switching to RadioHead lib completely also didn't help
stevech wrote:maybe the wrong commands to the RFM69 are being used for deep sleep?

Currently I'm using LowPowerLab RFM69 library, which seem to handle switching modes quite similarly to RadioHead. There is some strange bit-magic happening though.


Not sure where that 0xE3 came from, but it appears that it filters out every OPMODE down to 0. (So all in all both implementations should be doing the same thing).
Anyway, i'll try with just writeReg(1, 0);
Just read that sleeping RFM69 module should drain 1uA at most, so there's something really wrong...
It seems that the cause of my problem is radio module.

I've desoldered every unnecessary piece from the board one by one, measuring power consumption between each step.
After desoldering RFM69W, consumption dropped to ~1uA.
I thought it might be damaged, so i've replaced it with a spare one. Consumption went back to 350uA.
It seems that separate circuit to power on/off RFM69 is necessary
I'm experiencing the same issue with very similar readings (0.38-0.4mA).

Interesting part is that powering through 3V3 pin increased drain by ~50uA, [450mA total] (tried both with and without regulator soldered).
However, when powering circuit with 5V on VIN pin everyting seems to work fine draining 1.5uA in sleep mode.

the code i'm running for test is:

There are no additional components attached to board during test.
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