Tiny Machine Basic

Enhanced version for the Industrologic T51 Single Board Computer

Software Reference Manual

Version 1/22/04

Industrologic, Inc.
3201 Highgate Lane
St. Charles, MO
63301
USA

Phone: (636) 723-4000
www.industrologic.com
info@industrologic.com




Trademark and Copyright Information

Tiny Machine Basic and TMB are Trademarks of Industrologic, Inc. 2002
This document is Copyright (c) 2002 by Industrologic, Inc.
All rights reserved.

No part of this manual may be reproduced or transmitted in any form or by any means, electronic or mechanical, including photocopying or scanning, for any purpose other than the personal use by the purchaser of this product. Industrologic, Inc. reserves the right to revise this document at any time without obligation to notify any person of such revision. Industrologic, Inc. assumes no responsibility for any errors that may appear in this document.

Warning/Disclaimer

Whereas effort has been made to make the information in this document as useful and accurate as possible, Industrologic, Inc. assumes no responsibility for the application, usefulness, or completeness, of the information contained herein. Under no circumstance will Industrologic, Inc. be responsible or liable for any damages or losses including indirect or consequential damages or losses arising from either the use of any information contained within this manual or the use of any products or services referenced within this manual.


Overview and General Information

Tiny Machine Basic (TMB) is a simple BASIC language interpreter with a limited syntax and list of instructions. TMB is not so much a high level language like most BASIC interpreters, but is a cross between BASIC and machine language. It has been written specifically for the 8 bit structure of the Intel 8051 instruction set compatible family of microcontrollers, and for program storage in a small serial EEPROM.

TMB includes features that make it easy to write and understand bit manipulation programs. When entering programs it will understand values entered in decimal or hexadecimal as well as single byte character strings. It also features commands that can change the display of number values from decimal to hexadecimal.

Instructions entered while programming are saved as two-byte tokenized instructions, not as BASIC source code, therefore, all instruction arguments and line numbers, are limited to a single byte, (values from 0 to 255). Values that exceed this limit at run time will "roll over" or "roll under" back to a byte value, and will not cause a run-time error.

Similarly, instructions that use a limited range of values and are given values outside that range will not cause a run-time error, but will either ignore the instruction or convert the illegal value to a legal value.

A "command" consists of an instruction and its single byte "argument", and will be performed as soon as entered. A program line entry consists of a number from 1 to 255, a space, an instruction, and a single byte argument.

Lower case characters are converted to upper case when typed since all instructions must be in upper case.

Line numbers and arguments are always a single byte and can be entered as decimal values, e.g. x xx xxx xD xxD xxxD, hexadecimal values, e.g. xH xxH, or quoted single character strings, e.g. "x".

Instructions that manipulate the ports of the microcontroller must be used in ways that are compatible with the port hardware. If any bit of P1 or P3 is to be used as an input, it must be to a logic level "high" state, or "1". (On power up the port pins are set high.)

Comments may be added to program files created and saved on a host computer and uploaded, but the program saved in the microcontroller will not contain comments. Comments must be on separate lines, and any line that does not begin with a program line number may be a comment. When comment lines are sent to the microcontroller during program upload, syntax errors occur, and the lines are ignored.


Variables

The following is a list of variables in TMB-Enhanced which are byte values that can be read or assigned values by the user program.

A,B,C,D,E   general purpose byte variables where certain operations are performed
F,G,H,M,S   and where the results of certain operations are stored

P1          the byte value associated with port P1
The following are byte variables that can be read and displayed, but cannot be assigned values by the user program. The user program must read KEY and INT often enough to insure that they contain current and valid values.

KEY    the ASCII value of the last character received at the serial port and is
       cleared after being read (see Appendix A for a table of these values)
(A)    a special description of variable A used to display the ASCII
       character rather than the numeric value

Instructions

The following is a list of instructions where [arg] is an argument to the instruction in the form of a byte variable, number, or ASCII character.

The command instructions will normally be used only as a command at the prompt, and the rest of the instructions will normally be used in a program, but may be used as a command at the prompt to see how the instruction works.

Command instructions:

BAUD=[arg]     Set baud rate of serial port to [arg] times 100, and save in
               EEPROM. Allowable values are 192, 96, 48, 24, 12, 6, 3.

MODE=[arg]     Set communication mode (data bits and parity), and save in EEPROM.
               Allowable values are 80, 81, 82, 71, 72.
               80 = 8 data bits, no parity
               81 = 8 data bits, odd parity
               82 = 8 data bits, even parity
               71 = 7 data bits, odd parity
               72 = 7 data bits, even parity

The number of stop bits is always considered to be one. Although the microcontroller contains a hardware UART for sending and receiving serial data, it cannot provide all of the combinations of data bits, stop bits, and parity bit that more advanced UART's can provide. There is no communication error checking when receiving characters in TMB-Enhanced. Note: If you change the baud rate or communication mode in TMB-Enhanced, you will also need to change it in your terminal software!


Examples:
BAUD=96        set serial port baud rate to 9600
MODE=71        set data bits to 7 and parity to odd


BOOTON         Run your program when TMB starts (i.e., on power up)
BOOTOFF        Turn off the BOOTON feature (both are saved in EEPROM)
NEW            Erase all program lines
LIST           Display the program lines (if there are more than 20 lines the
               listing will pause until you press a key)
RUN            Run the program from the command prompt (>)
END            Stop the program and return to the prompt
Control C (pressing the "C" key while the CTRL key is already pressed) will cause a running program to stop. The program can be stopped with the END instruction, by having no further lines to execute, (possibly by going to a non-existant line number above the rest of the lines), or by telling the program to go to line zero. If the program does not have a method of exiting in response to some program condition, the power will need to be cycled to return to the prompt.

Control and program flow instructions:

DELAY [arg]    Pause the program for [arg] tenths (1/10) of a second
GOTO [arg]     Jump to the instructions beginning at line number [arg]
GOSUB [arg]    Call subroutine at line number [arg] (1 layer deep only)
RETURN         Return to next instruction after the last GOSUB
LOOP [arg]     Begin a loop with [arg] iterations (1 layer deep only)
ENDLOOP        Terminate a loop
Subroutines and loops may only be one layer deep, that is, a subroutine may not contain another GOSUB instruction, and an ENDLOOP instruction must be performed before another LOOP instruction is performed.


Examples:
DELAY 255      delay 25.5 seconds

1 GOSUB 10     call subroutine at line 10
2 GOTO 1       jump to line 1
10 PRINT "A"   send an upper case A to the serial port
11 RETURN      jump to line following the GOSUB instruction

10 GOSUB A     call subroutine at the line number of the value of variable A
               (if the value of A is 20 it would be the same as GOSUB 20)

1 LOOP 255     start a loop of 255
2 PRINT "A"    send an upper case "A" to the serial port
3 ENDLOOP      jump back to line 2 until 255 loops have been done

Display and keyboard instructions (serial port):

PRINT [arg]    Display a byte value in decimal/hexadecimal, or as character
               This instruction sends characters out the serial port
               (see Appendix A for a table of these values)

The PRINT instruction does not include a carriage return/line feed sequence (13D/10D or 0DH/0AH) after displaying a value or character like most BASIC languages. If either of these characters are desired they will need to be displayed separately. The PRINT instruction, when in HEX mode, will always display values with two digits followed by "H".

Lower case characters are converted to upper case when typed since all instructions must be in upper case. If a lower case displayable character is used as a value argument, the ASCII code must be used since it cannot be enclosed in quotes. For example, to print an "a" you must use PRINT 97 or PRINT 61H.

HEX            Display values in hexadecimal (try this at the command prompt)
DECIMAL        Display values in decimal (returns it to normal)
INPUT [arg]    Wait for a value to be entered (followed by a carriage return) and
               then put the value in [arg]. This instruction waits for characters
               from the serial port. (see Appendix A for a table of these values)

The ESCAPE key will cancel value entry with the INPUT instruction, (but not stop the program)


Examples:
PRINT 0DH      send a carriage return to the serial port
PRINT 13       send a carriage return to the serial port
PRINT 0AH      send a line feed to the serial port
PRINT 10       send a line feed to the serial port
PRINT "A"      send an upper case A to the serial port
PRINT 65       send an upper case A to the serial port
PRINT 97       send a lower case A to the serial port
INPUT A        wait for a value and then set variable A to that value
 
A=66           ASCII code for 'B"
PRINT (A)      send ASCII character "B" to serial port

A=[arg]        Set byte variable A to [arg]
A=A+[arg]      Add the value in [arg] to variable A
A=A-[arg]      Subtract the value in [arg] from variable A
A=A*[arg]      Multiply variable A by the value in [arg]
A=A/[arg]      Divide variable A by the value in [arg], (remainder is discarded)
A=A\[arg]      Remainder of dividing variable A by the value in [arg]

IF A=0 [arg]   If variable A is zero jump to line number [arg]
IF A<>0 [arg]  If variable A is not zero jump to line number [arg]
IF A=B [arg]   If variable A equals variable B jump to line number [arg]
IF A<>B [arg]  If variable A does not equal variable B jump to line number [arg]
IF A<B [arg}   If variable A is less than variable B jump to line number [arg]
IF A>B [arg]   If variable A is greater than variable B jump to line number [arg]


Examples:
A=KEY          get value of last character at Serial Port 1
A=A-66         subtract the ASCII value for "B", which is 66
IF A=0 30      if character was "B" then jump to line 30

A=A+B          add the value of variable B to variable A
A=A+10         add 10 to variable A (e.g., if A contained 10 it would
               become 20, if A contained 255 it would roll over to 9)
A=A-1          subtract 1 from A (e.g., if A contained 2 it would
               become 1, if A contained 0 it would roll under to 255)
A=A*10         multiply variable A by 10 (e.g., if A contained 10 it would
               become 100, if A contained 30 it would roll over to 44)
A=A/5          divide variable A by 5 (e.g., if A contained 10 it would
               become 2, if A contained 202 it would become 40)
A=A\7          divide variable A by 7 and return the remainder in variable A
               (e.g., if A contained 10 it would become 3, if A contained 21 it
               would become 0)

IF A=0 10      if variable A is equal to 0 then jump to line 10
IF A<>0 15     if variable A is not equal to 0 then jump to line 15
IF A<B 20      if variable A is less than variable B then jump to line 20

Port instructions:

P1=[arg]          Set port P1 to [arg]
P1.X=[arg]        Set port P1 bit X (0-7) to [arg] (0 or 1)
P3.7=[arg]        Set port P3 bit 7 to [arg] (0 or 1)


Examples:
P1=1              set P1 bit 0 high, the other bits low
P1=80H            set P1 bit 7 high, the other bits low
P1.7=0            set P1 bit 7 low
P3.7=1            set P7.3 high

If any port bit is to be used as an input, it must be set high, (its power up setting.)

IF P1.0=0 [arg]   If port P1 bit 0 is low jump to line number [arg]
IF P1.0=1 [arg]   If port P1 bit 0 is high jump to line number [arg]
IF P1.1=0 [arg]   If port P1 bit 1 is low jump to line number [arg]
IF P1.1=1 [arg]   If port P1 bit 1 is high jump to line number [arg]
IF P1.2=0 [arg]   If port P1 bit 2 is low jump to line number [arg]
IF P1.2=1 [arg]   If port P1 bit 2 is high jump to line number [arg]
IF P1.3=0 [arg]   If port P1 bit 3 is low jump to line number [arg]
IF P1.3=1 [arg]   If port P1 bit 3 is high jump to line number [arg]
IF P1.4=0 [arg]   If port P1 bit 4 is low jump to line number [arg]
IF P1.4=1 [arg]   If port P1 bit 4 is high jump to line number [arg]
IF P1.5=0 [arg]   If port P1 bit 5 is low jump to line number [arg]
IF P1.5=1 [arg]   If port P1 bit 5 is high jump to line number [arg]
IF P1.6=0 [arg]   If port P1 bit 6 is low jump to line number [arg]
IF P1.6=1 [arg]   If port P1 bit 6 is high jump to line number [arg]
IF P1.7=0 [arg]   If port P1 bit 7 is low jump to line number [arg]
IF P1.7=1 [arg]   If port P1 bit 7 is high jump to line number [arg]
IF P3.7=0 [arg]   If port P3 bit 7 is low jump to line number [arg]
IF P3.7=1 [arg]   If port P3 bit 7 is high jump to line number [arg]


Example:
P3.7=1            set P3 bit 7 high for use as an input
IF P3.7=0 100     if P3 bit 7 is low jump to line number 100

T51-LCD instructions:

The LCD instructions apply not only to the Industrologic T51-LCD, but to any LCD module connected to the T51 in the same manner as the T51-LCD, that is, with the same connections made to the digital I/O signals. The LCD instructions manipulate only the I/O signals used to control the LCD so that any remaining signals may be used as general purpose I/O signals.

These instructions, particularly the initialization sequence, involve LCD signal timing and delays, and therefore take a relatively long time to complete compared to other instructions.

LCDCMD=[arg]   Send the command byte [arg] to the LCD. Refer to the data sheet of
               the LCD module used for the list of command values and their effects.
               (Many LCD's have similar commands which are shown in the examples.)

Examples:
LCDCMD=0       When this value is used, the LCDCMD instruction configures the
               digital I/O signals used for the T51-LCD, initializes the display,
               turns on the cursor, and sets the cursor to blink. This instruction
               and value must be used before using any other LCD instruction.
LCDCMD=1       Clear LCD display
LCDCMD=2       Set cursor to "home" position
LCDCMD=8       Display off
LCDCMD=12      Display on, cursor off
LCDCMD=13      Display on, cursor off, blinking of cursor position character on
               (large block)
LCDCMD=14      Display on, cursor on, cursor position character does not blink
               (underline)
LCDCMD=15      Display on, cursor on, blinking of cursor position character on
               (large block)
LCDCMD=16      Move cursor left
LCDCMD=20      Move cursor right

LCDCMD=24      Scroll display left
LCDCMD=30      Scroll display right


LCDPRN [arg]   Display a byte value at the next cursor location on the LCD in
               decimal or hexadecimal, or as a character. This instruction works
               just like the PRINT instruction, but for the LCD. For formatting
               details see PRINT.

LCDCUR=[arg]   Move the LCD cursor to position [arg]. Refer to the data sheet of
               the LCD module used to determine which line and column of the LCD
               correspond to a particular cursor position.

T51-LED instructions:

The LED instructions apply only to the four character Industrologic T51-LED. These instructions manipulate only the digital I/O used to control the T51-LED so that any remaining signals may be used as general purpose I/O signals.

The normal operation of the LED print commands is to scroll characters to the left when the next position to display a character is the rightmost position. The Clear and Home commands can be used to change the display position.

LEDCMD=[arg]   Send a special command [arg] to the LED.


Examples:
LEDCMD=0       When this value is used, the LEDCMD instruction configures the
               digital I/O signals used for the T51-LED, clears the display, sets
               the next display position to the leftmost position, and turns off
               both discrete LED's between the displays. This instruction and
               value must be used before using any other LED instruction.
LEDCMD=1       Clear/home the T51-LED display and turn off both discrete LED's
LEDCMD=2       Set next display position to the leftmost position (home)
LEDCMD=3       Turn off both discrete LED's
LEDCMD=4       Turn on only the bottom discrete LED
LEDCMD=5       Turn on only the top discrete LED
LEDCMD=6       Turn on both discrete LED's


LEDPRN [arg]   Display a byte value at the next display position on the T51-LED
               in decimal or hexadecimal, or as a character. This instruction works
               just like the PRINT instruction, but for the T51-LED. For
               formatting details see PRINT.

Timer instructions

TMB-Enhanced includes software countdown timers that can be individually set for periods of up to 255 hours, 255 minutes, or 255 seconds. Unlike the DELAY instruction, which pauses the program while waiting for the time to elapse, the countdown timers can be set, and will then run in the background. They can then be tested periodically while the program continues to see if they have timed out.

Note: Beginning with version 2.0, the number of timers has been reduced to two.

SETTIMER 1          set timer #1 from the values in variables H, M, and S
                    where H=hours, M=minutes, and S=seconds
SETTIMER 2          set timer #2

For versions prior to 2.0 only:
SETTIMER 3          set timer #3
SETTIMER 4          set timer #4

CLEARTIMER 1        turn off timer #1 so that it can no longer cause a timeout
CLEARTIMER 2        turn off timer #2 so that it can no longer cause a timeout

For versions prior to 2.0 only:
CLEARTIMER 3        turn off timer #3 so that it can no longer cause a timeout
CLEARTIMER 4        turn off timer #4 so that it can no longer cause a timeout

IF TIMER1=0 [arg]   If timer #1 has not timed out jump to line number [arg]
IF TIMER1=1 [arg]   If timer #1 has timed out jump to line number [arg]
IF TIMER2=0 [arg]   If timer #2 has not timed out jump to line number [arg]
IF TIMER2=1 [arg]   If timer #2 has timed out jump to line number [arg]

For versions prior to 2.0 only:
IF TIMER3=0 [arg]   If timer #3 has not timed out jump to line number [arg]
IF TIMER3=1 [arg]   If timer #3 has timed out jump to line number [arg]
IF TIMER4=0 [arg]   If timer #4 has not timed out jump to line number [arg]
IF TIMER4=1 [arg]   If timer #4 has timed out jump to line number [arg]


Example:
H=0                 zero hours
M=30                30 minutes
S=0                 zero seconds
SETTIMER 1          set timer #1 to timeout after 30 seconds

IF TIMER1=1 100     if timer #1 times out go to line number 100

Real-Time Clock instructions:

TMB-Enhanced includes a real-time clock that can be both set and read. Since the microcontroller does not have a battery backup system the clock will not retain its time if power is removed. When power is applied the clock will be set to zero hours, minutes, and seconds, and will begin keeping time even if a program is not running. The time can then be set if desired at the prompt or when a program is running. Since the clock is software based, its accuracy is dependent on components on the microcontroller board and will vary from unit to unit. Adjustments can be made in the program to improve accuracy on a particular board.

SETCLOCK            set clock from the values in variables H, M, and S
                    where H=hours, M=minutes, and S=seconds
READCLOCK           read clock and place the values into variables H, M, and S
                    where H=hours, M=minutes, and S=seconds

Examples:
H=23                23 hundred hours
M=0                 zero minutes
S=0                 zero seconds
SETCLOCK            set clock to 11PM even

READCLOCK           read clock values
PRINT H             display hours
PRINT ":"
PRINT M             display minutes
PRINT ":"
PRINT S             display seconds

EEPROM instructions:

Part of the EEPROM used to store the TMB-Enhanced user program can also be used to store program data such as configuration information that must be saved if the power is removed from the microcontroller. EEPROM addresses 1 through 255 correspond to TMB line numbers 1 through 255. Using an EEPROM address will cause it to not be available for program line storage and will overwrite any program line stored there. Likewise, entering a program line at an EEPROM address will overwrite the data stored there.

When data is written to an EEPROM address, it is likely that the data will represent program instructions and arguments, which TMB-RC51 will attempt to RUN and LIST. In order to prevent the program from running this data as an instruction, an END instruction must be placed at a line number lower than any data address used so that the program will stop before reaching the data. If this is not done, the program may do any number of undesirable things, e.g., erasing itself or changing the baud rate unexpectedly. It is also suggested that the highest possible EEPROM addresses be used for data so that it is LISTED after the normal program lines.

Most EEPROMs may be written over a million times, but even this limit could be exceeded if the program wrote to the EEPROM in an unintended loop caused by incorrect programming, so some caution should be used. EEPROMs may be read an unlimited number of times.

WRITEEE [arg]  Write the 2 byte values in variables A and B to the EEPROM word at
               address [arg], where [arg] is an address from 1 to 255

READEE [arg]   Read the EEPROM word at address [arg] and put the 2 byte values in
               variables A and B, where [arg] is an address from 1 to 255

Examples:
A=FFH          set variable A value
B=FFH          set variable B value
WRITTEE 250    write A and B to memory location 250
READEE 255     read memory location 255 and place in variables A and B

Appendix A

The following is a table of character codes and their equivalent (ASCII) characters. These values are useful when using the PRINT instruction or when testing variables (like the variable KEY) for a specific character.

Decimal          Control Char. Control      Decimal               Decimal
Value   Character  Abbreviation  Key        Value   Character     Value   Character
-------------------------------------------------------------------------------------------
00      NULL                NUL  ^@         45      - (hyphen)    90      Z    
01      START OF HEADING    SOH  ^A         46      . (period)    91      [ (left bracket)
02      START OF TEXT       STX  ^B         47      /             92      \ (backslash)
03      END OF TEXT         ETX  ^C         48      0             93      ] (right bracket)
04      END OF TRANSMIT     EOT  ^D         49      1             94      ^ (carat)
05      ENQUIRY             ENQ  ^E         50      2             95      _ (underscore)
06      ACKNOWLEDGE         ACK  ^F         51      3             96      ` (accent)
07      BEEP                BEL  ^G         52      4             97      a
08      BACK SPACE          BS   ^H         53      5             98      b
09      HORIZONTAL TAB      HT   ^I         54      6             99      c
10      LINE FEED           LF   ^J         55      7             100     d
11      VERTICAL TAB        VT   ^K         56      8             101     e
12      FORM FEED           FF   ^L         57      9             102     f
13      CARRIAGE RETURN     CR   ^M         58      :             103     g
14      SHIFT OUT           SO   ^N         59      ;             104     h
15      SHIFT IN            SI   ^O         60      <             105     i
15      DEVICE LINK ESC     DLE  ^P         61      =             106     j
17      DC1 X-ON            DC1  ^Q         62      >             107     k
18      DC2                 DC2  ^R         63      ?             108     l
19      DC3 X-OFF           DC3  ^S         64      @             109     m
20      DC4                 DC4  ^T         65      A             110     n
21      NEG. ACKNOWLEDGE    NAK  ^U         66      B             111     o
22      SYNC. IDLE          SYN  ^V         67      C             112     p
23      END OF TX BLOCK     ETB  ^W         68      D             113     q
24      CANCEL              CAN  ^X         69      E             114     r
25      END MEDIUM          EM   ^Y         70      F             115     s
26      SUBSTITUTE          SUB  ^Z         71      G             116     t
27      ESCAPE              ESC             72      H             117     u
28      RIGHT ARROW (on PC)                 73      I             118     v
29      LEFT ARROW  (on PC)                 74      J             119     w
30      UP ARROW    (on PC)                 75      K             120     x
31      DOWN ARROW  (on PC)                 76      L             121     y
32      BLANK SPACE                         77      M             122     z
33      !                                   78      N             123     { (left brace)
34      " (double quote)                    79      O             124     | (vertical bar) 
35      # (number sign)                     80      P             125     } (right brace)
36      $                                   81      Q             126     ~ (tilde)
37      %                                   82      R             127     DELETE
38      &                                   83      S
39      ' (single quote)                    84      T
40      ( (open parenthesis)                85      U
41      ) (close parenthesis)               86      V
42      *                                   87      W
43      +                                   88      X
44      , (comma)                           89      Y


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