Файл: The Microcontroller Idea book (Jan Akelson, 1997).pdf

ONERR line number

R

Passes control to line number following an arithmetic error. Arithmetic errors in-

clude ARITH. OVERFLOW, ARITH. UNDERFLOW, DIVIDE BY ZERO, and

BAD ARGUMENT.

ONEX1 line number

R

On interrupt 1 (pin 13), BASIC-52 finishes executing the current statement, and

then passes control to an interrupt routine beginning at line number. The interrupt

routine must end with RETI.

ONTIME number of seconds, line number

R

When TIME = number of seconds, BASIC-52 passes control to an interrupt rou-

tine beginning at line number. The interrupt routine must end with RETI.

CLOCK1 starts the timer.

expression .OR. expression

C,R

Logical OR

P.

same as PRINT

PCON

C,R

Retrieves or assigns a value to the 8052’s special function register PCON.

PGM

C,R

Programs an EPROM, EEPROM, or NV RAM with data from memory. The fol-

lowing data must be stored in internal data memory in the locations listed:

1Bh,19h

High byte, low byte of first address of data to program

1Ah,18h

High byte, low byte of first address to be programmed - 1

1Fh,1Eh

High byte, low byte indicating number of bytes to program

40h,41h

High byte, low byte indicating width of programming pulse.

High byte = ((65536 - pulse width in seconds * XTAL/12) / 256.

Low byte = ((65536 - pulse width in seconds * XTAL/12) .AND. 0FFh.

26h

For Intelligent programming, set bit 3.

For 50-millisecond programming, clear bit 3.

PH0.

C,R

Same as PRINT, but displays values in hexadecimal format. Uses two digits to

display values less than 0FFh.

PH0.#

C,R

Same as PRINT#, but displays values in PH0. hexadecimal format

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Programming

PH0.@

C,R

Same as PRINT@, but outputs values in PH0. hexadecimal format.

PH1.

C,R

Same as PRINT, but displays values in hexadecimal format. Always displays

four digits.

PH1.#

C,R

Same as PRINT#, but displays values in PH1. hexadecimal format.

PH1.@

C,R

Same as PRINT@, but outputs values in

PH1. hexadecimal format.

PI

C,R

Constant equal to 3.1415926.

POP variable [,...variable]

C,R

Assigns the value of the top of the argument stack to variable.

PORT1

C,R

Retrieves or assigns a value to PORT1 (pins 1-8).

PRINT [expression] [,...expression] [,]

C,R

PRINT#

C,R

Same as PRINT, but outputs to LPT (pin 8). BAUD and XTAL values affect the

PRINT# rate.

PRINT@

C,R

Same as PRINT, but outputs to a user-defined output driver. Requires an assem-

bly-language output routine at 403Ch in external program memory. Setting bit 7

of internal data memory location 24h enables the output routine.

PROG

C

Stores the current RAM program in the EPROM space.

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PROG1

C

Saves the serial-port baud rate. On power-up or reset, BASIC-52 boots without

having to receive a space character. The terminal’s baud rate must match the

stored value.

PROG2

C

Like PROG1, but on power-up or reset, BASIC-52 also begins executing the first

program in the EPROM space.

PROG3

C

Like PROG1, but also saves MTOP. On power-up or reset, BASIC-52 clears

memory only to MTOP.

PROG4

C

Like PROG2, but also saves MTOP. On power-up or reset, BASIC-52 clears

memory only to MTOP.

PROG5

C

Like PROG3, but also reads 5Fh in external data memory on power-up or reset.

If 5Fh contains 0A5h, BASIC-52 doesn’t clear external data memory. If data

memory location 5Eh contains 34h, BASIC-52 will automatically begin execut-

ing a program in external data memory.

PROG6

C

Like PROG5, but if external data memory location contains 5Fh, BASIC-52 calls

a user-written assembly-language reset routine beginning at program memory

4039h.

PUSH expression [,...expression]

C,R

Places the values of expression(s) sequentially on BASIC-52’s argument stack.

PWM expression1, expression2, expression3

C,R

Outputs a pulse-width modulated (PWM) sequence of pulses on pin 3. Expres-

sion1 is the width of each high pulse, expressed in clock cycles. Expression2 is

the width of each low pulse, expressed in clock cycles. Expression3 is the number

of PWM cycles output. One clock cycle = 12/XTAL. One PWM cycle = one high

pulse plus one low pulse. Expression1 and Expression2 must each be at least 25.

Maximum for each Expression is 65535.

RAM

C

Selects the current program in the RAM space.

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RCAP2

C,R

Retrieves or assigns a value to the 8052’s special function registers RCAP2H and

RCAP2L.

READ variable [,...,variable]

R

Retrieves the expressions in a DATA statement and assigns each expression to a

variable.

REM

C,R

Introduces a comment, or remark. BASIC-52 ignores all text after

REM in a pro-

gram line.

RESTORE

R

Resets READ pointer to the first expression in the DATA statement.

RETI

R

Returns program control to the line number following the most recently executed

ONEX1 or ONTIME statement.

RETURN

R

Returns program control to the line number following the most recently executed

GOSUB statement.

RND

C,R

Returns a pseudo-random number between 0 and 1 inclusive.

ROM [program number]

C

Selects a program in the EPROM space (beginning at 8000h). Default program

number is 1.

RROM [program number]

C,R

Changes to ROM mode and runs the specified program. Default program number

is 1.

RUN

R

Executes the current program. Clears all variables.

SGN (expression)

C,R

Returns +1 if expression >=0, zero if expression = 0, and -1 if expression <0.

SIN(expression)

C,R

Returns the sine of expression

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Example:

PRINT “hello”,SPC(3),"good-by"

hello

good-by

SQR(expression)

C,R

Returns square root of expression.

ST@ expression

C,R

Copies a 6-byte floating-point number from the argument stack to external data

memory. Expression points to the most significant byte of the number.

STOP

Halts program execution.

STRING expressions, expression2

C,R

Allocates memory for strings (variables each consisting of a series of text charac-

ters).

Expression1 = (Expression2 * number of strings) + 1.

Expression2 = maximum number of bytes (characters) per string + 1. Executing

STRING clears all variables. Maximum number of strings is 255.

Examples:

STRING 91,9

reserves space for ten 8-character strings

STRING 9,4

reserves space for two 3-character strings

T2CON

C,R

Retrieves or assigns a value to the 8052’s special function register T2CON.

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