add a lot to the ceaser cipher

ceaser.asm

@@ -1,18 +1,23 @@
 .ORIG x3000
 
-	LEA R0, START  	;load the address of the label START into R0
-	PUTS            ;output the string at START
 
-	BEGIN
-	LEA R0, ENCRYPTTYPE  	;load the address of the label ENCRYPTTYPE into R0
-	PUTS            		;output the string at START
+ENCRYPTTYPE   .STRINGZ  "Would you like to encode? or decode? E or D?\n"
+ENCRYPTmsg    .STRINGZ  "Nice. made it te ENCRYPT.\n"
+DECRYPTmsg    .STRINGZ  "You are the decrypting master.\n"
+  LEA R0, START   ;load the address of the label START into R0
+  PUTS            ;output the string at START
+
+  BEGIN
+  LEA R0, ENCRYPTTYPE   ;load the address of the label ENCRYPTTYPE into R0
+  PUTS                ;output the string at START
 
 ; Figures out if the user wanted to encrypt or decrypt a message.
 ; If 'E' then encrypt. If 'D' then decrypt.
 ; Another option (not implemented) was to branch to decrypt if not encrypt.
+
 checkChar:
-  in                ; Read in a single character to R0.
-  add r3, r0, #0	; Copy R0 to R3.
+  in              ; Read in a single character to R0.
+  add r3, r0, #0  ; Copy R0 to R3.
   lea r6, neg69   ; Load address of neg69 into R6.
   ldr r6, r6, #0  ; Load contents of neg69 into R6 (R6 now holds -69).
   add r0, r3, r6  ; Add -69 to the value in R3, to check if it's 'E'.
@@ -23,99 +28,158 @@ checkChar:
   add r0, r3, r6  ; Add -68 to the value in R3, to check if it's 'D'.
   BRz decrypt     ; If zero, branch to decrypt.
 
-  LEA R0, INVALID  	;load the address of the label INVALID into R0
-  PUTS            	;output the string at START
+  LEA R0, INVALID   ;load the address of the label INVALID into R0
+  PUTS              ;output the string at START
 
   BR checkChar
-
+neg69:  .FILL #-69  ; Constant for the inverse of 'E'.
+neg68:  .FILL #-68  ; Constant for the inverse of' D'.
 decrypt:
-	LEA R0, DECRYPTmsg  	;load the address of the label START into R0
-	PUTS            	;output the string at START
-	BR close
+  LEA R0, DECRYPTmsg    ;load the address of the label START into R0
+  PUTS              ;output the string at START
+  BR CeaserLoop
 
 encrypt:
-	LEA R0, ENCRYPTmsg  	;load the address of the label START into R0
-	PUTS            	;output the string at START
-	BR close
-
-readString:  
-    LEA r2, stringSize  ; Saves the address of stringSize into r2 
-    LD r1, stringLoop ; Loads the number 20 in register 1
-  loop:
-      in ; Gets and prints out each characer
-      STR r0, r2, #0 ;Saves the value of the input(r0) in memory.
-      ADD r2, r2, #1 ; adds one to the memory address in r2
-      ADD r1, r1, #-1 ; counts down the loop
-  BRp loop ; Breaks the loop if zero
-    LEA r0, stringSize ; saves the string locaiton in r0
-    PUTS ; prints out the characters
-BR close 
-
-close:
-	HALT
+  LEA R0, ENCRYPTmsg    ;load the address of the label START into R0
+  PUTS              ;output the string at START
+  BR CeaserLoop
 
-START 			.STRINGZ	"Welcome to the Ceaser Cipher Program\n"
-ENCRYPTTYPE 	.STRINGZ	"Would you like to encode? or decode? E or D?\n"
-KEY				.STRINGZ	"Please Enter the Key. 1 to 26: \n"
-ENCRYPTmsg 		.STRINGZ	"Nice. made it te ENCRYPT.\n"
-DECRYPTmsg 		.STRINGZ	"You are the decrypting master.\n"
-INVALID			.STRINGZ	"You have input an invalid answer.\n"
+;;;; CEASER LOOP ;;;;
+enterMessage:       .STRINGZ "Please enter your message: "
 
-neg69:  .fill	#-69  ; Constant for the inverse of 'E'.
-neg68:  .fill	#-68  ; Constant for the inverse of' D'.
-
-array:  .blkw	20    ; Array of size 20.
-
-; **** readString *****
-stringLoop:   .FILL 20 ; Sets the maximum character fill limit to be 20 characters
-stringSize:   .blkw 20 ; Saves a memoery size of 20.
+CeaserLoop:
+AND R1, R1, #0    ; clear r1 with 0;
 
+LEA R0, enterMessage   ;load the address of the label START into R0
+PUTS            ;output the string at START
+loop:
+ ;Get Character and save in R3
+  ;GETC            ; input character -> r0
 
 Letters:
-  LD r1, capitalLetterBottom ; fill register r1 with letter A
-  LD r2, capitalLetterTop ; fill register r2 with letter Z
-  IN ; loads in letter and outputs it.
+  LD r2, capitalLetterBottom ; fill register r1 with letter A
+  LD r6, capitalLetterTop ; fill register r2 with letter Z
+  GETC ; loads in letter R0 and outputs it.
   NOT r3, r0 ; Gives one compliment of r0 stores in r3
   ADD r3, r3, #1 ; ADDS one to make the number negitive
-  ADD r1, r3, r1 ; adds value of r3 (negitive r0) to r1 and stores in r1
+  ADD r2, r3, r2 ; adds value of r3 (negitive r0) to r1 and stores in r1
   BRn CapitalTop ; br if value of letter greater than A
   BRz SuccessInput ; br if value is equal to A
   BR FailedInput ; If it was a value less than A output Failed message 
   
 CapitalTop:
-    ADD r2, r3, r2 ; adds negitive value of r3 (not r0) to r2 and stores in r2
+    ADD r6, r3, r6 ; adds negitive value of r3 (not r0) to r2 and stores in r2
     BRzp SuccessInput ; the letter is Z
     
 LowerCaseLetter:
-  LD r1, lowerCaseBottom ; fill register r1 with Letter a
-  LD r2, lowerCaseTop ; fill register r2 with Letter z
-  ADD r1, r3, r1 ; adds value of r3 (negitive r0) to r1 and stores in r1
+  LD r2, lowerCaseBottom ; fill register r1 with Letter a
+  LD r6, lowerCaseTop ; fill register r2 with Letter z
+  ADD r2, r3, r2 ; adds value of r3 (negitive r0) to r1 and stores in r1
   BRn lowerTop ; br if value of letter greater than A
   BRz SuccessInput ; br if value is equal to A
   BR FailedInput ; If it was a value less than A output Failed message
 
 lowerTop:
-ADD r2, r3, r2 ; adds negitive value of r3 (not r0) to r2 and stores in r2
+ADD r6, r3, r6 ; adds negitive value of r3 (not r0) to r2 and stores in r2
 BRzp SuccessInput ; the letter is Z
 BR FailedInput
 
-SuccessInput:
-  OUT
-  LEA r0, successmsg ; loads failure message
-  PUTS
-  HALT
 FailedInput:
-  OUT
-  LEA r0, failuremsg ; loads failure message
-  PUTS
-  HALT
+  BR endLoop ;
 
-successmsg:       .STRINGZ "YOU input WAS a valid letter!"
-failuremsg:       .STRINGZ "Your input was not a valid letter."     
+START       .STRINGZ  "Welcome to the Ceaser Cipher Program\n"
+INVALID     .STRINGZ  "You have input an invalid answer.\n"
 capitalLetterBottom:  .FILL x0041 ; Letter A
 capitalLetterTop:   .FILL x005A ; Letter Z
 lowerCaseBottom:    .FILL x0061 ; Letter a
 lowerCaseTop:     .FILL x007A ; Letter z
+failuremsg:       .STRINGZ "Your input was not a valid letter."       
+stringLoop:   .FILL 20 ; Sets the maximum character fill limit to be 20 characters
+string:        .blkw 21 ; Saves a memoery size of 20.
+key:          .fill #13 ; Temproray key 
+numLoop:      .FILL #20  ;
+LD R5, numLoop ;
+
+AND R6, R6, #0    ; clear r1 with 0;
+AND R3, R3, #0    ; clear r1 with 0;
+AND R0, R0, #0    ; clear r1 with 0;
+AND R2, R2, #0    ; clear r1 with 0;
+neg10:  .fill #-10  ; Constant for the inverse of '\n'.
+
+SuccessInput:
+  add r3, r0, #0  ; Copy R0 to R3. (Save input Charater to R3)
+
+ ;loop counter
+  ADD R5, R5, #-1 ;
+  BRz endLoop ;
+
+ ;print out character
+  ADD r0, r3, #0  ; load charater -> r0
+  out               ; r0 -> console
+
+;begin keying
+  ; load z into r0
+  lea r6, lowerCaseTop  ; Load address of key into R6.
+  ldr r6, r6, #0        ; Load contents of key into R6.
+  ; make r6 negative: -("z")
+  NOT R6, R6            ; Gives one compliment of the "z" stores in r6
+  ADD r6, r6, #1        ; ADDS one to make the number negitive
+
+  ; load key into r4.
+  lea r4, key           ; Load address of key into R4.
+  ldr r4, r4, #0        ; Load contents of key into R4.
+
+  ; check if key is bigger than character bounds. 
+  ADD r0, r3, r4 ; add charater and key.
+  ADD r0, r0, r6 ; Add Key+Character to r0 (top "z")
+  BRp Overflow
+
+save:
+  ADD r3, r3, r4 ;    add character and key and save in r0
+  LEA R0, string ; saves the address of the storage memory block
+  ADD R0, R0, R1 ;
+  STR R3, R0, #0       ; r3 -> ( memory address stored in r0 + r1 )
+  ADD R1, R1, #1       ; increments the memory pointer so that it
+                       ; always points at the next available block
+  BR loop
+
+Overflow:
+  ; make r3 (character) negative
+  NOT r0, r3; Gives one compliment of the "z" stores in r0
+  ADD r0, r0, #1 ; ADDS one to make the number negitive
+  ; load lowerCaseTop to r6p
+  lea r6, lowerCaseTop  ; Load address of key into R6.
+  ldr r6, r6, #0        ; Load contents of key into R6.
+  ; k = k - (lowerCaseTop+1-C)
+  ADD r6, r6, #1 ; lowerCaseTop +1
+  ADD r0, r6, r0 ; r2 - C
+  ;make r0 negative
+  NOT r0, r0; Gives one compliment of the "z" stores in r0
+  ADD r0, r0, #1 ; ADDS one to make the number negitive
+  ; k + r0
+  ADD r4, r4, r0 ; Add the Key + r0 and save in r4
+
+  ; c = bottom.
+  ; load lowerCaseBottom to r6p
+  lea r6, lowerCaseBottom  ; Load address of key into R3.
+  ldr r3, r6, #0        ; Load contents of key into R3.
+
+  BR save ;
+
+endLoop:
+  LEA R0, endmsg   ;load the address of the label START into R0
+  PUTS            ;output the string at START
+  LEA R0, string   ;load the address of the label string into R0
+  PUTS                ;output the string at string
+  LEA R0, byemsg   ;load the address of the label START into R0
+  PUTS            ;output the string at START
+  HALT
+
+close:
+  HALT
+
+endmsg:       .STRINGZ "\nYour encoded/decoded messages is: "
+byemsg:       .STRINGZ "\nThank you. Have a nice day."
 
 
 .END