- Tue Jun 16, 2015 2:35 am
#20570
I suggest you buy a prop guard 
What do you use to monitor the WiFi traffic?
What do you use to monitor the WiFi traffic?
- Tue Jun 16, 2015 2:49 am
#20571
speaking about cheaper part: is it possible to replace the AVR with a cheaper MCU?
The ATTINY441 is listed @ $1.65 on DK. I am thinking of an EFM8BB10 @$0.42.
The ATTINY441 is listed @ $1.65 on DK. I am thinking of an EFM8BB10 @$0.42.
- Tue Jun 16, 2015 9:41 am
#20598
I have one. I didn't think about it till now.
cnping https://github.com/cnlohr/cnping ... you also might like https://github.com/cnlohr/wifirxpower
I've never seen that chip. Though I dislike th 8051 ISA (it's what I first learned and coded in assembly when I was growing up), I would be more than happy to bury the hatchet... On that chip from a technical aspect, it looks as though the only concerns I would have is:
Not 5V tolerant, so it would have to be behind one of my voltage regulators, which means it wouldn't be able to control them.
Would require external voltage divider to monitor the vBat vs the ATTiny which just monitors Vcc against the internal reference.
After some googling I was unable to come up with any I2C Slave examples for that part.
It doesn't look like it has very protected I/O pins.
Soooooo If you wanted to tackle problem 3, and turn it into a splendid I2C Controlled PWM device, I would certainly consider nixing the ATTiny for this thing.
Squonk wrote:I suggest you buy a prop guard
I have one. I didn't think about it till now.
Squonk wrote:What do you use to monitor the WiFi traffic?
cnping https://github.com/cnlohr/cnping ... you also might like https://github.com/cnlohr/wifirxpower
Squonk wrote:speaking about cheaper part: is it possible to replace the AVR with a cheaper MCU?
The ATTINY441 is listed @ $1.65 on DK. I am thinking of an EFM8BB10 @$0.42.
I've never seen that chip. Though I dislike th 8051 ISA (it's what I first learned and coded in assembly when I was growing up), I would be more than happy to bury the hatchet... On that chip from a technical aspect, it looks as though the only concerns I would have is:
Not 5V tolerant, so it would have to be behind one of my voltage regulators, which means it wouldn't be able to control them.
Would require external voltage divider to monitor the vBat vs the ATTiny which just monitors Vcc against the internal reference.
After some googling I was unable to come up with any I2C Slave examples for that part.
It doesn't look like it has very protected I/O pins.
Soooooo If you wanted to tackle problem 3, and turn it into a splendid I2C Controlled PWM device, I would certainly consider nixing the ATTiny for this thing.
- Tue Jun 16, 2015 5:11 pm
#20637
Thanks!
It is 5V tolerant, from EFMBB1 datasheet, Absolute Maximum Ratings states that:
Voltage on I/O pins or RST V IN if:
But why do you need 5V in the first place, and what is the point controlling the LDOs?
IIRC, there is a single LDO on the original Hubsan board, and everything is powered from it.
Not a big deal
The EFM8 series was released only early this year (February 2015), and SiLabs is publishing new examples on a regular basis since then, but no I2C example yet. However, the chip is able to do I2C master or slave, of course.
Again, as this is rather new chip, I would be shocked if it is not at least 2kV ESD capable.
I have nothing against AVRs, but for this price, you could get much better and/or cheaper MCUs, including some 8-bit or 32-bit Kinetis ARM Cortex M0+ from Freescale, EFM8 from SiLabs, PIC16 from Microchip, a few RL78 from Renesas, some eZ8 from Zilog, STM32F0 from ST and even cheaper AVR parts!
So, do you have any particular reason to stick to the ATTiny441?
I am just trying to optimize the design (difficult!), either by lowering its price, or by providing better performance for the same price. Regarding the MCU, you could either divide the price by 3, or get a nice 32-bit MCU for better fail-safe mode, IMU, data logger, etc.
On a totally different subject, it would be nice to control the copter from an iOS or Android phone app by using the integrated accelero/gyro/touch screen over WiFi... Any experience with this?
cnlohr wrote:Squonk wrote:What do you use to monitor the WiFi traffic?
cnping https://github.com/cnlohr/cnping ... you also might like https://github.com/cnlohr/wifirxpower
Thanks!
cnlohr wrote:Squonk wrote:speaking about cheaper part: is it possible to replace the AVR with a cheaper MCU?
The ATTINY441 is listed @ $1.65 on DK. I am thinking of an EFM8BB10 @$0.42.
I've never seen that chip. Though I dislike th 8051 ISA (it's what I first learned and coded in assembly when I was growing up), I would be more than happy to bury the hatchet... On that chip from a technical aspect, it looks as though the only concerns I would have is:
Not 5V tolerant, so it would have to be behind one of my voltage regulators, which means it wouldn't be able to control them.
It is 5V tolerant, from EFMBB1 datasheet, Absolute Maximum Ratings states that:
Voltage on I/O pins or RST V IN if:
- VDD ≥ 3.3 V: GND–0.3 to 5.8 V
- VDD < 3.3 V: GND–0.3 to VDD +2.5 V
But why do you need 5V in the first place, and what is the point controlling the LDOs?
IIRC, there is a single LDO on the original Hubsan board, and everything is powered from it.
cnlohr wrote:Would require external voltage divider to monitor the vBat vs the ATTiny which just monitors Vcc against the internal reference.
Not a big deal
cnlohr wrote:After some googling I was unable to come up with any I2C Slave examples for that part.
The EFM8 series was released only early this year (February 2015), and SiLabs is publishing new examples on a regular basis since then, but no I2C example yet. However, the chip is able to do I2C master or slave, of course.
cnlohr wrote:It doesn't look like it has very protected I/O pins.
Again, as this is rather new chip, I would be shocked if it is not at least 2kV ESD capable.
cnlohr wrote:Soooooo If you wanted to tackle problem 3, and turn it into a splendid I2C Controlled PWM device, I would certainly consider nixing the ATTiny for this thing.
I have nothing against AVRs, but for this price, you could get much better and/or cheaper MCUs, including some 8-bit or 32-bit Kinetis ARM Cortex M0+ from Freescale, EFM8 from SiLabs, PIC16 from Microchip, a few RL78 from Renesas, some eZ8 from Zilog, STM32F0 from ST and even cheaper AVR parts!
So, do you have any particular reason to stick to the ATTiny441?
I am just trying to optimize the design (difficult!), either by lowering its price, or by providing better performance for the same price. Regarding the MCU, you could either divide the price by 3, or get a nice 32-bit MCU for better fail-safe mode, IMU, data logger, etc.
On a totally different subject, it would be nice to control the copter from an iOS or Android phone app by using the integrated accelero/gyro/touch screen over WiFi... Any experience with this?
