Got the Manchester library working + RF communication scheme

After re-installing the libraries and switching to the Arduino IDE 1.06, I managed to get the ATtiny85 to transmit a short array of characters to the receiver attached to the Arduino UNO.

Previously, I was having problems with getting the receiver to receive any meaningful data, but I think the problem might have been because of omitting the following line in the code which was only needed if the ATtiny85 was working on 1Mhz internal clock.

man.workAround1MhzTinyCore(); //add this in order for transmitter to work with 1Mhz Attiny85/84

I was very sure I had burned the bootloader to 8Mhz, but for some unknown reason, it just needed that line of code. After that, it worked, as shown in this video of LED lights lighting up in sync:


The problem with using RF is that the data sent is received by all receivers of the same frequency. The receivers and transmitters that I have were all 413Hz, so I drafted up with this communication scheme that would help me communicate with the right diamond:

format of arrays: `[char1, char2, checksum]`

where `checksum = (((dec(char1)*dec(char2))*13)%8+81`

correct array: `['A', 'G', 'M']`

"A" --> 65
"G" --> 71
checksum = 84 --> "T"

table of codes
A (65) - identity

B (66) - identity

C (67) - identity

D (68) - identity

E (69) - identity

F (70) - identity

G (71) - frequency1 (Min working voltage)

H (72) - frequency2

I (73) - frequency3

J (74) - frequency4

K (75) - frequency5

L (76) - frequency6

M (77) - frequency7

N (78) - frequency8

O (79) - frequency9

P (80) - frequency10 (Max working voltage)

Q (81) - switch on/off

R (82) - checksum

S (83) - checksum

T (84) - checksum

U (85) - checksum

V (86) - checksum

W (87) - checksum

X (88) - checksum

Y (89) - checksum

Z (90) - affirmative

algorithm for communication between diamond and dock

diamond idle state:
transmit '[identification, frequency, checksum]' (2 seconds) --> receive (2 seconds) (repeatedly).
if receive same array as transmitted:
transmits [identification, affirmative, checksum] and goes to setting state.

diamond setting state:
stops transmitting for 20 seconds (only receives).
if receives [identification, frequency, checksum]:
sets new frequency and resets timer for 20 seconds.
else if 20 seconds is up:
goes to idle state.


dock (on menu for changing frequency) idle state:
only receives
if receives correct array:
goes to setting state.

dock (on menu for changing frequency) waiting state:
transmits same array once --> wait to receive affirmative (1 second) (repeatedly for 3 seconds)
if received affirmative: 
goes to setting state.
else if 3 seconds is up without receiving affirmative:
goes to idle state.

dock (on menu for changing frequency) setting state:
user can select new frequency, transmits [identification, new frequency, checksum]
if send affirmative to diamond (to exit):
goes to idle state.

And I got the RF to send bytes:

COM4 6_12_2016 10_09_15 PM.png

Posted in PC

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