Grove encoder with GrovePi+[SOLVED]

Archives GrovePi
1

Hi

Can you provide me a example for the Grove Encoder (D2) connected to GrovePi+ board?
I tried following code but I always receive zeros.

import time
import grovepi
import atexit

atexit.register(grovepi.encoder_dis)

print "Reading from the encoder"
grovepi.encoder_en()
while True:
try:
[new_val,encoder_val] = grovepi.encoderRead()
if new_val:
print encoder_val
time.sleep(.5)

except IOError:
    print ("Error")"

and this is definations;
"def encoder_en():
write_i2c_block(address, encoder_en_cmd + [unused, unused, unused])
time.sleep(.2)

def encoder_dis():
write_i2c_block(address, encoder_dis_cmd + [unused, unused, unused])
time.sleep(.2)

def encoderRead():
write_i2c_block(address, encoder_read_cmd + [unused, unused, unused])
time.sleep(.2)
data_back= bus.read_i2c_block_data(address, 1)[0:2]
#print data_back
if data_back[0]!=255:
return [data_back[0],data_back[1]]
else:
return [-1,-1]
"

If you can also suggest how to change D2 to other port to test the GrovePi+ or Grove encoder has a problem.

Thank you

2

Hi,
The Grove encoder only works with firmware version 1.2.5 and up. Can you make sure that you have it on your Pi: https://github.com/DexterInd/GrovePi/tree/master/Firmware/Source/v1.2/grove_pi_v1_2_5 and run a firmware update to upload it to the Atmega using: avrdude -c gpio -p m328p -U flash:w:grove_pi_v1_2_5.cpp.hex . After uploading the firmware, make sure that it is on there by running: https://github.com/DexterInd/GrovePi/blob/master/Software/Python/grove_firmware_version_check.py . Once the firmware is updated, connect the encoder to port D2 and try running this https://github.com/DexterInd/GrovePi/blob/master/Software/Python/grove_encoder_read.py.

Do let us know if this helps.

-Karan

3

Hi Karan,

Can you please give instructions for uploading firmware.

4

Hey Sam,
Make sure that you have the latest version of the GrovePi repository on the Raspberry Pi.

Go to the firmware folder: Grovepi/Firmware/Source/v1.2/grove_pi_v1_2_5 . It should look like this: https://github.com/DexterInd/GrovePi/tree/master/Firmware/Source/v1.2/grove_pi_v1_2_5 .

Double-check that this file is there: grove_pi_v1_2_5.cpp.hex

Run the firmware update using: avrdude -c gpio -p m328p -U flash:w:grove_pi_v1_2_5.cpp.hex.

Once the firmware update is done, run the grove_firmware_version_check.py in the Grovepi/Software/Python folder and make sure that it shows 1.2.5.

-Karan

5

Hi Karan

Do I need to follow this as well - http://www.dexterindustries.com/GrovePi/get-started-with-the-grovepi/updating-firmware/

Regards,
Sam

6

Not since you have a GrovePi+. The old GrovePi-without-plus needed that to be able to be flashed with avrdude.

7

Thank you Karan & Mirar,

Can you please advice how do I port Grove encoder to D3 or D4 port?

Thank you
I manage to update firmware sucessfully.

8

Hey Sam,
The Grove encoder can only work on Port 2 because it needs interrupts to work and the pins on Port 2 are the only ones that support it.

-Karan

9

Thank you Karan.