Quick start Rz

This short article will help you to learn Rz language quickly.  Here are the list of distinct features of Rz (version 3.6).

1  Rz is quite like C with only integer type.
2  Global variables must be declared.  Local variables are automatic.
3  An array must be global.
4  Pass reference by &v.

A session in Rz

    Try to compile "fac.txt" shown here:

// factorial

fac(n)
  if( n == 0 ) return 1
  else return n * fac(n-1)

main()
  print(fac(6))
 
    Here is the command line and the output at the screen:

C:\rz36\test>rz36 fac.txt
.symbol
 ...
.code 0
 ...
 jal rads main
 trap r0 #0
; fun fac pv 1
:fac
st r1 @1 fp
...
eq r2 r1 #0
jf r2 L102
mov retval #1
jmp L101
jmp L103
:L102
sub r3 r1 #1
push sp r3
jal rads fac
mul r2 r1 r28
mov retval r2
jmp L101
:L103
:L101
ld rads @0 fp
...
ret rads
; fun main pv 0
:main
...
mov r1 #6
push sp r1
jal rads fac
trap r28 #1
:L104
...
ret rads
.data 200
.end

C:\rz36-3\test>
 . . . 
   
Now to run the program, you compile the source and save it in  "out.txt" which is an assembly language file.  Then, use an assembler "as21.exe" to compile it into an object file (machine code), "out.obj".  Use a simulator "sim21.exe" to load and run this object file.  To see a list of available command in the simulator use "h".  Use "q" to exit from the simulator.

C:\rz36-3\test>rz36 fac.txt >out.txt

C:\rz36-3\test>as21 out.txt

C:\rz36-3\test>sim21 out.obj
load program, last address 200
>t
PC   0 mov r30 #3500     r0:0 r1:0 r2:0 r3:0 r4:0 r5:0 r6:0 r7:0 r8:0 r9:0
                         r27:0 r28:0 r29:0 r30:3500 r31:0
>t
PC   1 mov r29 #3000     r0:0 r1:0 r2:0 r3:0 r4:0 r5:0 r6:0 r7:0 r8:0 r9:0
                         r27:0 r28:0 r29:3000 r30:3500 r31:0
>t
PC   2 jal r27 27        r0:0 r1:0 r2:0 r3:0 r4:0 r5:0 r6:0 r7:0 r8:0 r9:0
                         r27:3 r28:0 r29:3000 r30:3500 r31:0
>t
PC  27 st r1 @1 r30      r0:0 r1:0 r2:0 r3:0 r4:0 r5:0 r6:0 r7:0 r8:0 r9:0
                         r27:3 r28:0 r29:3000 r30:3500 r31:0
>g
720 stop, clock 151, execute 151 instructions
. . .

C:\rz36-3\test>


That's it.  Enjoy!

Examples

Ex1.  To add one to ten.

main()
  i = 1
  s = 0
  while( i <= 10 )
    s = s + i
    i = i + 1
  print(s)

Ex2.  Find a maximum value in an array.

ax[10]    // declare an array size 10

// max of array a size n
max(a, n)  
  m = a[0]
  i = 1
  while( i < n )
    if( m < a[i] ) m = a[i]
    i = i + 1
  return m


// initialise array
init(a, n)
  i = 0
  while( i < n )
    a[i] = i + 10
    i = i + 1

main()
  init(&ax,10)          // pass ref of ax
  print(max(&ax,10))

Ex3.  Recursive function

// factorial

fac(n)
  if( n == 0 ) return 1
  else return n * fac(n-1)


main()
  print(fac(6))

Ex4.  Making and printing a linked list of integer

cell[1000]
freecell     // cell storage

// access functions
head(a)
  return cell[a]
tail(a)
  return cell[a+1]
sethead(a,i)
  cell[a] = i
settail(a,i)
  cell[a+1] = i

newnode(i)    // get a new node, with i
  p = freecell
  freecell = freecell + 2
  if( freecell > 10000 ) print("no more cell")
  sethead(p,i)
  settail(p,0)
  return p


// link node a to list m
insert(m,a)
  settail(a,tail(m))
  settail(m,a)


// print item in list recursively
prlist2(m)
  if( m != 0 )
    print(head(m)," ")
    prlist2(tail(m))

// main print list, skip header node
prlist(m)
  prlist2(tail(m))

main()
  h = newnode(0)       // make header
  insert(h,newnode(1))
  insert(h,newnode(2))
  insert(h,newnode(3))
  prlist(h)


last update  20 Aug 2017