Sheet feeder, image recording apparatus having the sheet feeder, and computer-readable medium therefor

A non-transitory computer-readable medium storing computer-readable instructions that are executable by a processor coupled with a sheet feeder, the sheet feeder comprising:

• a tray having a supporter configured to support a sheet placed on the tray;
• a roller disposed in a position contactable with the supporter, the roller being configured to, when rotating in a particular direction, feed the sheet supported by the supporter, in a conveyance direction along a conveyance path;
• a motor configured to generate a driving force to rotate the roller in the particular direction;
• a first sensor configured to detect a rotational quantity of the roller;
• and
• a second sensor configured to detect that the sheet reaches a particular position on the conveyance path, the instructions being configured to, when executed by the processor, cause the processor to perform a particular process comprising:
• a driving process comprising:
• supplying the motor with an electric current;
• a stopping process comprising:
• in response to determining that the motor has not rotated before the second sensor detects that the sheet reaches the particular position, stopping supplying the electric current to the motor;
• a setting process comprising:
• when an accumulated rotational quantity of the roller is less than a threshold, setting a retry upper limit to a first value, wherein the accumulated rotational quantity is detected by the first sensor in the driving process performed for a first time after a beginning of the particular process, and the first value is equal to or more than one;
• and
• when the accumulated rotational quantity of the roller is equal to or more than the threshold, setting the retry upper limit to a second value more than the first value;
• and
• repeatedly performing the driving process and the stopping process until a number of retries to perform the driving process reaches the retry upper limit or until the second sensor detects that the sheet reaches the particular position.