BASIC stamp manual v2.2

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5: BASIC Stamp Command Reference – TOGGLE

BASIC Stamp Syntax and Reference Manual 2.2 • www.parallax.com • Page 455

TOGGLE

BS1 BS2 BS2e BS2sx BS2p BS2pe BS2px

TOGGLE Pin

Function

Invert the state of an output pin.

• Pin is a variable/constant/expression (0 – 15) that specifies which

I/O pin to switch logic state. This pin will be placed into output

mode.

Quick Facts

Table 5.122: TOGGLE Quick

Facts.

BS1 All BS2 Models

Affected

PINS OUTS

Commands

HIGH and LOW

Explanation

TOGGLE sets a pin to output mode and inverts the output state of the pin,

changing 0 to 1 and 1 to 0.

In some situations TOGGLE may appear to have no effect on a pin’s state.

For example, suppose pin 2 is in input mode and pulled to +5V by a 10k

resistor. Then the following code executes:

DIR2 = 0 ' make P2 an input

PIN2 = 0 ' make P2 output driver low

DEBUG PIN2 ' show P2 state (1 due to pull-up)

TOGGLE 2 ' toggle P2

DEBUG PIN2 ' show P2 state (1 again)

- or -

DIR2 = 0 ' make P2 an input

OUT2 = 0 ' make P2 output driver low

DEBUG ? IN2 ' show P2 state (1 due to pull-up)

TOGGLE 2 ' toggle P2

DEBUG ? IN2 ' show P2 state (1 again)

The state of pin 2 doesn’t change; it's high (due to the resistor) before

TOGGLE, and it’s high (due to the pin being output high) afterward. The

point is that TOGGLE works on the OUTS register (PINS on the BS1),

which may not match the pin’s state when the pin is initially an input. To

NOTE: Expressions are not allowed as

arguments on the BS1. The range of

the Pin argument on the BS1 is 0 – 7.

All