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Overview

This is just a quick reference for what Parsnip supports. Some of this is likely to change; this project is a work-in-progress. As well, I will likely not keep this up-to-date as I am more focused on the parser. These commands are more to test the parser and show off in screenshots what is possible.

Types

Parsnip features a bunch of variable types, with plans for some more core types.

  • ui8, ui16, ui32 are the unsigned integers, where Parsnip generally defaults to ui16. At this moment, signed integer types aren't supported, but they are planned. (It's a bit tedious, and right now I'm focusing on the parser itself).
  • true and false are boolean types. When converted to a string, they display true and false, respectively, but evaluate to 1 and 0 for math. Ex., 3+(1=1) returns 4 as you might expect in TI-BASIC.
  • xfloat and single are float types, where Parsnip defaults to xfloat, a higher-precision 80-bit float. Most of the math commands support single types, but I don't think I have anything that outputs a single type to be used, yet.
  • fixed1616 and fixed88 are somewhat supported. These are fixed-point formats, and just as a proof-of-concept, integer division returns a fixed1616 if it doesn't divide evenly.
  • string is a string type.
  • char is a 1-byte character.
  • raw is for raw data. Currently, this is what the sprite routine requires.
  • list is a list of values that can be various types (even other lists).

Operations

Create a list with []. For example:

["HELLO","WORLD","!",3.14]→Z
Disp Z

Use [] to index. Adding to the previous code to display "HELLO":

Disp Z[0]

You can also index strings. Since Z[1] is a string:

Disp Z[1][2]

That prints the char W, since Z[1] == "WORLD", and index [2] refers to the 'R'.

You can store to a list element, but that is kind of broken:

3.14159→Z[3]

You can't overwrite with a different-sized element, so Parsnip will make an attempt to fit it to the size. For example, if you try to write a float to a ui16, Parsnip will convert the float to a ui16.

Strings are strange, if you initially store a 5-character string to an element, all future strings stored to it must fit within 5 characters. Storing to list elements will eventually change, and elements will be resized according to the new type, but for now, this is what you have to work with.

Math Operators

I have programmed in:

  • →, store the value to a var. Currently allows single-character names, A through Z and theta.
  • +
  • -
  • *
  • /, currently returns a fixed 16.16 if not an integer.
  • ^, returns a float
  • √(, returns a float
  • e^(, returns a float
  • ln(), returns a float
  • 2 (squared)
  • 3 (cubed)
  • -1, returns a float
  • int(val) converts to a 32-bit unsigned integer, or 16-bit unsigned if small enough.
  • (-), negation.
  • =
  • ≠
  • >
  • ≥
  • <
  • ≤

""

"string" is a string and must have a closing quote.

Lbl, Goto

These work as in TI-BASIC, but you can be more creative with the names. In the future, the allowed chars will probably be restricted to alphanumeric.

Repeat loop

Works like in TI-BASIC.

While loop

Works like in TI-BASIC.

If... [ElseIf]... [Else]... End

If you want code to execute only if a condition is true:

:If <<condition>>
:<<code>>
:End

For example, suppose you want to increment x if [Enter] is pressed (note that [Enter] is a getKey() value of 9):

:If getKey(9)
:x+1→x
:End

(this is not the most efficient way, you can do x+getKey(9)→x)

If you want to display "Hello" if K=0, or "World" otherwise, you can use Else:

:If K=0
:Disp "Hello"
:Else
:Disp "World"
:End

If you want to display "Hello" if K=0, and "World" if K=1, you can use ElseIf. Note that there are more efficient ways to do this particular example:

:If K=0
:Disp "Hello"
:ElseIf K=1
:Disp "World"
:End

At this stage of the parser, ElseIf is the Else token followed by the If token.

If you want to display "Hello" if K=0, "World" if K=1, and ":)" otherwise, then you can use Else with ElseIf

:If K=0
:Disp "Hello"
:ElseIf K=1
:Disp "World"
:Else
;Disp ":)"
:End

ClrDraw, ClrHome

These work basically like in TI-BASIC, but of course ClrDraw doesn't also update the LCD (like how Axe and Grammer do it).

DispGraph

Copies the contents of the graph screen to the LCD.

Disp

Displays a value on the homescreen.

Text()

Text(Y,X,value) Displays a value on the graph screen at pixel coordinates, using a small font.

NOTE: This might change in the future, specifically the default font and coordinate system for text.

Pause

Waits for [Enter] to be pressed.

getKey()

getKey() returns the current key press. getKey(val) returns true if the key is being pressed, else false.

raw()

raw("hexadecimal string") converts a string of hexadecimal digits to raw bytes. Currently useful for sprite data

Sprite()

Sprite(raw,y,x,method) draws an 8x8 sprite using the first 8 bytes of raw at (y,x) pixel coordinates, using method:

  • 0 - Overwrite
  • 1 - AND logic
  • 2 - XOR logic
  • 3 - OR logic
  • 5 - Erase logic

NOTE: In the future, this will change; in particular, a raw type variable will not be used.

Pixel-On() -Off() -Change() -Test()

Works like in TI-BASIC, except pxl-Test() returns true/false instead of 1/0. (However, for math purposes, true and false evaluate to 1 and 0.)

Full

Sets 15MHz mode. TI-BASIC automatically sets 15MHz mode.

Fix

Works similar to TI-BASIC, but not the same. This sets the max number of digits when displaying a float.

Version

This returns the string containing Parsnip's version. Example usage:

Disp VERSION

Get/Set Modes

These functions aren't useful and are almost certain to change in functionality.

GETMODE() returns an integer that represents the current mode. SETMODE(val) sets the mode. The current modes (and these will almost certainly change):

  • 1 : InvertTextFlag - Inverts text drawn to the graph screen.
  • 2 : InvertLCDFlag - Dispgraph inverts the data before outputting to the LCD.
  • 4 : OnBlockFlag - Disables checking for the [ON] key to exit

Add their values to set multiple modes. For example, to set all three:

SETMODE(7)

Set Font

SETFONT(val) can be used to set a font to be used on the graph screen. The syntax of this command is almost certain to change in the future. Fonts may change. Font alignment may change.

  • SETFONT(0) is a small font (4x6). Text columns are aligned to 4 pixels. That means, for example, Text(Y,1,"?" will draw at pixel coordinates x=4, and Text(Y,3,"?" will draw at pixel coordinates x=12, and so on.
  • SETFONT(1) this is a variable-width large font.
  • SETFONT(2) this also uses the small font, but you can draw text to pixel coordinates. Default

LCD commands

The built-in var, LCD is a display type. On the TI-83+/84+ series, you can:

  • LCD.OFF() to turn the LCD off
  • LCD.ON() to turn the LCD on
  • LCD.CONTRAST(val) to set teh contrast (0 to 63)
  • LCD.ZSHIFT(val) to set the z-shift value (0 to 63, if you don't know what this is, definitely play with this.
  • LCD.FLIP(val) on some calculators, the LCD has special commands to flip the LCD horizontally and vertically. This could be useful, but remember that not all calcs have this.

I don't know how useful this is, but you can also do something like LCD→Z, which means now you can use any of the commands via Z.

CHAR()

CHAR(val) converts val to a char. For example, to display the @ symbol:

Disp CHAR(64)

Or if you want to put an '@' before the string "HELLO":

Disp CHAR(64)+"HELLO"