====== IanalogWrite2f() ======

''IanalogWrite2f()'' converts a user floating-point value to the 4~20mA output range.

{{:en-us_commands:reference:ianalogwrite2f.svg?900|IanalogWrite2f command operation flow}}

''void IanalogWrite2f(uint8_t ch, float min, float max, float value)''

===== Commands =====

^ Command ^ Arguments ^ Return Value ^ Operation ^
| ''IanalogWrite2f(ch, min, max, value)'' | ''uint8_t ch'' — MPINO: analog pin such as ''A0''; MPAINO: overall module channel number starting at ''0''\\ ''float min''\\ ''float max''\\ ''float value'' — Output value expressed in the ''min'' ~ ''max'' range | ''void'' | Converts a user floating-point value to the 4~20mA output range. |


===== Example =====

Connect a Y output module to MPAINO-8A8R(T) and select **Analog Output Module → Y**. Set the CH0 DIP switch to OFF and measure the 4–20mA output at ''I+'' and ''−''.

<code cpp>
void setup() {}

void loop() {
  IanalogWrite2f(0, 0.0F, 100.0F, 25.0F);  // Scale 25% to the 4–20mA range and output about 8mA.
  delay(500);
}
</code>

===== Precautions =====

  * Set the MPAINO Y module CH0 DIP switch to OFF and connect the 4–20mA output to ''I+'' and ''−''.
  * An input of approximately 3.6~4.0mA returns the normal value ''0''; inputs below 3.6mA return an error value.
  * Error values help detect open circuits. The user must implement final alarms and safety actions in the program.
  * ''IanalogRead2()'' and ''IanalogRead2f()'' also return ''65535'' on error, rather than a user-range value. Check for errors before using the result.
  * The full ''int32_t'' range is available for ''min~max'' in ''IanalogRead2()'', but if the normal range includes ''65535'', it cannot be distinguished from an error value.
  * ''analogRead2Avgf()'' uses state and a buffer separate from ''analogRead2Avg()''. Using both increases SRAM usage.
  * If ''samples'' is ''0'' or memory allocation fails in ''analogRead2Avgf()'', it returns the current valid corrected value as a ''float''.
  * On MPINO, do not use ''analogRead2()'' on voltage/NTC channels that are not 4~20mA inputs.
  * For MPINO products requiring ''analogReference(EXTERNAL)'', set it first in ''setup()''.
  * ''IanalogWrite2()'' and ''IanalogWrite2f()'' are convenience outputs dedicated to 4~20mA. Avoid alternating them with ''IanalogWrite()'' on the same channel.
  * The analog output circuit requires an external 12~24V supply. USB power alone may not provide normal output.
  * Verify actual current input/output with measuring instruments after preparing a test product.

===== Built-in Commands in the Same Category =====

  * [[:en-us_commands:reference:analogwrite2|analogWrite2() View detailed description]]
  * [[:en-us_commands:reference:ianalogwrite2|IanalogWrite2() View detailed description]]

[[:en-us_commands:builtin|← Built-in Command List]]