when Aseba Studio connects to a robot, it enumerates the available variables, functions and events from the robot itself. This API is different for different robots, or for different versions of the firmware of one robot. Aseba studio then compiles according to this API.
When you save the binary code to an SD card, this code was compiled for a specific robot and firmware version. the robot checks if the code you have on an sd card is compatible with its firmware; if not, it wil not start.

The events (including the timer) happen when certain conditions are met, but they do not interrupt the code that is executed. A block of code is executed, and once it is done, the next block is executed if another event was triggered in the meantime.

In your code, you have a while loop which can only be exited if you press the center button. in this loop, pressing left or right sets the motor speed, and the length of the timer, but the timer event cannot be executed until you exit the while loop. It cannot interrupt.

Here is an example of code that behaves more like you intended I hope:

var state=0 onevent buttons when button.center == 1 do state=0 timer.period[0]=0 motor.left.target = 0 motor.right.target = 0 call leds.top(32,0,0) end when button.forward == 1 do call leds.top(6,26,0) state=1 end if state==1 then when button.right == 1 do motor.right.target = -100 timer.period[0] = 1000 call leds.top(32,13,0) end if button.left == 1 then motor.right.target = 100 timer.period[0] = 1000 call leds.top(32,26,0) end end onevent timer0 motor.left.target = 0 motor.right.target = 0 timer.period[0]=0 call leds.top(6,6,32)

I've got this program (code below) that isn't working as expected. There must me something wrong with the timer. Could you help me find out what?

Scenario:
The forward button is pressed, then the right button is pressed.

Actual result:
The right wheel start turning and keep turning indefinitely.

Expected result:
The right wheel starts turning and then stops after one second.

Program:

onevent button.center when button.center == 1 do motor.left.target = 0 motor.right.target = 0 call leds.top(32,0,0) end onevent button.forward when button.forward == 1 do call leds.top(6,26,0) while not (button.center == 1) do if button.right == 1 then motor.right.target = -100 timer.period[0] = 1000 call leds.top(32,13,0) end if button.left == 1 then motor.right.target = 100 timer.period[0] = 1000 call leds.top(32,26,0) end end end onevent timer0 motor.left.target = 0 motor.right.target = 0 call leds.top(6,6,32)

Best regards,
Emmanuel

var mot_l
var mot_r

1. Variables for Braitenberg avoid routine

var avoid_l[5] = [2, 0, -1, -5, -10]
var avoid_r[5] = [-10, -5, -2, 0, 2]
var avoid_shift = 4
var avoid_offset = MAX_SPEED*2/5

callsub init

sub init
call leds.temperature(0,0)

sub braitenberg_avoid
# Use the vector dot product to calculate motor values
call math.dot(mot_l, avoid_l, prox.horizontal[0:4], avoid_shift)
mot_l += avoid_offset
call math.dot(mot_r, avoid_r, prox.horizontal[0:4], avoid_shift)
mot_r += avoid_offset

# If motor values are < -MAX_SPEED or > +MAX_SPEED fix them
call math.clamp(mot_l, -MAX_SPEED, mot_l, MAX_SPEED)
call math.clamp(mot_r, -MAX_SPEED, mot_r, MAX_SPEED)

# Write calculated motor values to Thymio variables to run motors
motor.left.target = mot_l
motor.right.target = mot_r

onevent prox
callsub braitenberg_avoid

yes, there are hidden variables with values from all 7 sensors. In the view menu of aseba you can choose to show the hidden variables. The oens you need are:
prox.comm.rx._intensities
prox.comm.rx._payloads

im working on a little project where I control the Thymio with Python and a Raspberry Pi.

I know how to set the values for the motors:

value = 250 network.SetVariable("thymio-II", "motor.left.target", [value])

But how can I read the values from the proximity sensors with python?
I tried this but this is not working:

network.GetVariable("thymio-II", "prox.horizontal[2]")

Does someone has an idea?

Thanks.

I also thought of combining incoming ir with proximity sensors but the looks like the range wont allow that. Even if that works, such a solution is a hack and not a proper solution to access the incoming signals directionally.

Please let me know if I am missing something! I would appreciate the help. Thanks!

on which page did you find this code? which barcode were you using?

with Thymio it is difficult to measure a distance, as there are no sensors to do so. You could however program a line following, and estimate the time it would take to drive 60 cm. Then, you program the robot to drive straight until it sees a line, then follow it and start the timer, stop when the timer reaches the set time.

How would I do this?

If a line is detected at any point, the robot should immediately turn right and follow the line for a given distance of 60cm.

Thanks
David

### VARIABLES DECLARATION ###
var running = 1
var counter = 0
var state
var intensityDiff
var code
#Colors tables
var r[]=[OFF,OFF,OFF,OFF,ON,ON,ON,ON]
var g[]=[OFF,OFF,ON,ON,OFF,OFF,ON,ON]
var b[]=[OFF,ON,OFF,ON,OFF,ON,OFF,ON]

call leds.top(r[code], g[code], b[code])
#0=colorless,1=blue,2=green,3=lightblue,4=red,5=darkpink,6=yellow,7=purple

### TURNING OFF THE LEDs ###
call leds.prox.v(0,0)
call leds.prox.h(0,0,0,0,0,0,0,0)
call leds.top(0,0,0)
call leds.temperature(0,0)

### EVENT BUTTON FORWARD ###
onevent button.forward

1. starts line tracking and waits for sync bit

if button.forward == 1 then
running = 1
state = S_WAIT_SYNC
end

### EVENT BUTTON CENTER ###
onevent button.center
#stops running and motors, turns LEDs off
if button.center == 1 then
running = 0
motor.left.target = 0
motor.right.target = 0
call leds.top(0,0,0)
end

### EVENT PROXIMITY SENSORS (EVERY 100 ms => 10 Hz)###
onevent prox
#if the robot is running, steering and bar code reading are activated
#we use the prox.ground.delta[1] to steer, the …[0] to check the bar code

if running == 1 then

### STEERING PART ###
intensityDiff = prox.ground.delta[1]-525
#speed of robot is adjusted to keep around a gray mean value. If
#difference is too important, the robot spins until it finds the line
#again. The steering is controled by the gray gradient of the trail.
if abs(intensityDiff) < 170 then
motor.left.target = 115+intensityDiff/8
motor.right.target = 115-intensityDiff/8
else
motor.left.target = intensityDiff/4
motor.right.target = -intensityDiff/4
#edit to stop colours if line is lost
state = S_WAIT_SYNC
end

### BAR CODE CHECKING PART ###
#if Thymio is waiting for sync and crosses a black line, it starts bar
#code reading and turns LEDs off.
if state == S_WAIT_SYNC and prox.ground.delta[0] < BW_LIMIT then
state = S_READING
call leds.top(0,0,0)
counter = 0
emit data [prox.ground.delta[0],1000]
end
emit data [prox.ground.delta[0],0]
#if state is reading, the robot reads the bar code
if state == S_READING then

#we wait to count to 2 times the timer = 100 ms (counter is
#increment at the end of the code) so we are in the middle of the
#black sync box
if counter == 2 then
code=0
#we wait the first two counter + one INTERVAL (4 * 50ms) to measure
#the first block of bar code. This can be tuned to match with the
#speed of the robot
elseif counter == (2+INTERVAL) then
emit data [prox.ground.delta[0],1000]
#if bit is white set code to 1 (c0=001b)
if prox.ground.delta[0]>BW_LIMIT
then code=1
else code=0
end
#test again after another INTERVAL
elseif counter == (2+2*INTERVAL) then
emit data [prox.ground.delta[0],1000]
#if bit is white add 2^1 to code (c1=010b)
if prox.ground.delta[0]>BW_LIMIT
then code +=2
end
elseif counter == (2+3*INTERVAL) then
emit data [prox.ground.delta[0],1000]
#if bit is white add 2^2 to code (c2=100b)
if prox.ground.delta[0]>BW_LIMIT then code +=4
end

#LEDs are turned on according to binary code (c2 c1 c0)
call leds.top(r[code],g[code],b[code])
#again another INTERVAL and we go back to S_WAIT_SYNC to wait for
#the next bar code
elseif counter == (2+4*INTERVAL+3) then
state = S_WAIT_SYNC
end
counter += 1
else
call leds.circle(0,0,0,0,0,0,0,0)
end
end