BASIChat+ Explained

:"<>"→Str9
:0→θ
:10→dim(∟BCHAT
:ClrHome
:Output(8,1,"LOADING..."
:If not(sum(∟BCHAT
:Then
:ClrHome
:Input "USERNAME:",Str1
:length(Str1)→∟BCHAT(1
:If ∟BCHAT(1)>9
:9→∟BCHAT(1
:sub(Str1+"{^-1}{^-1}{^-1}{^-1}{^-1}{^-1}{^-1}{^-1}{^-1}",1,9)→Str1
:For(X,1,9
:inString("ABCDEFGHIJKLMNOPQRSTUVWXYZ .-+/º'()?",sub(Str1,X,1))→∟BCHAT(X+1)
:If not(∟BCHAT(X+1
:37→∟BCHAT(X+1
:End
:End
:"+"→Str2
:For(X,1,9)
:Str2+sub("ABCDEFGHIJKLMNOPQRSTUVWXYZ .-+/º'()??",∟BCHAT(X+1),1)→Str2
:End
:sub(Str2,2,∟BCHAT(1))→Str2
:sum(19,1
:Lbl X
:sum(19,0
:ClrHome
:Output(8,1,"BY CVSOFT v1.0-a"
:Stop
:Lbl H
:ClrHome
:If Str9≠"<>"
:Output(1,1,Str9
:Output(8,1,"SEND        EXIT"
:Lbl K
:0→X
:0→K
:Repeat K or X=33
:X+1→X
:getKey→K
:End
:If K=11 or K=21 or K=105
:Goto S
:If K=15 or K=22 or K=45
:Goto X
:Str9→Str8
:sum(18)
:If Str9≠Str8
:Goto H
:Goto K
:Lbl S
:ClrHome
:Input "<"+Str2+"> ",Str1
:"<"+Str2+"> "+Str1→Str1
:sum(18)
:sum(17,Str1
:Goto H

--------------------Explanation of code, in pseudocode--------------------

Store a dummy value to the received data string and store zero to device id
Define list BCHAT
If BCHAT is zero, then:
	Input a username
	Store the length of the username entry string to a maximum length of 9 characters
	Add a bunch of ^-1s to guarantee a length of 9 characters for substringing
	Convert the characters in the username to their positions in a string and store in the username list
	If not found in string, replace with "?"
(End If)
Define the username string
Convert the username list to a string with the inverse process for creation of the list
Substring any extra characters
Open the Calcnet2 link
Goto Homescreen

Label: eXit
Close Calcnet2 link
Stop execution

Label: Homescreen
Display recipient's calc ID in row 7
Display menu options in row 8
Label :Key_entry
Define getKey variable
Define counting variable
Loop until counting variable reaches 33 or a key is pressed
If [ENTER], [2nd], or [Y=] (Send menu item) is pressed, Goto Send
If [CLEAR], [MODE], or [GRAPH] (Exit menu item) is pressed, Goto eXit

(no usable key was pressed and/or counting variable reached 33)
Store last received data to a temporary string
Get the sent string from the other calculator
If the strings are the same, Goto Key-entry; Else, Goto Homescreen to update display

Label: Send
Input message
Add username in "<username> " format
(added in a later version)
Substring if longer than 120 characters (added in a later version)
Store remote device id to a temporary variable
Menu to select recipient: if broadcasted, store zero to theta; else, do nothing
(/added in a later version)
Calcnet2-Send the message with username attached
Restore theta to pre-send value
Goto Homescreen