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Power-On Self Test (POST)
The following tests are automatically performed when the printer is turned on.
•LEDs Test - Checks operation of LEDs on the operator panel. The LEDs turn on and off after the printer is turned on, then all LEDs turn on for a few seconds.
•RAM Test - Checks that the CPU can write/read the RAM.
•Font ROM/Microcode Sum Test - Checks that the ROM data is correct.
•Timer/Interrupt Controller Test - Checks that this function works.
•NVRAM Test - Checks that the NVRAM data is correct.
•Switch Scan Test - Checks the buttons on operator panel.
•Carrier Initialization - Carrier moves to the left to activate the home position sensor, then moves to the first print position.
•Feed Initialization - Form feed motor rotates forward and then backward.
If any errors occur during the POST tests, a combination of blinking LEDs indicates which test failed. See “Start” on page