ZD421 and ZD621 Desktop Printer User Guide

Standard Interface Controls

The printer's user interface is located on the top of the printer towards the front.

Standard Interface Controls
Icon	Button	Descriptions
	1. POWER button — Pressing this button turns power to the printer ON and OFF. Also used to initiate low-power sleep and wake states.	Initial power ON — Press POWER until the printer’s indicator lights flash on in various combinations for several seconds. This indicates the printer is performing self-diagnostics and configuration checks, and integrating optional components. The STATUS indicator turns solid green, indicating the printer is ready for normal print operations. Energy Star (low power mode) — To minimize power use, press and release POWER one time to place the printer in Energy Star low power mode. All the indicators will turn off except the STATUS Indicator which flashes to indicate the printer is in Energy Star Mode. Power OFF with Energy Star Delayed — Press and hold POWER for 4–9 seconds. You can start a batch print job and put the printer into the low power consumption state of Sleep mode after the job has finished. Power OFF / Shutdown — Press and hold POWER for 4–9 seconds to turn printer power OFF. Power Failure Recovery Mode — This printer feature is activated by a hardware jumper setting on one of the optional Printer Connectivity Modules installed in the printer. You can turn this mode on and off by activating the jumper. The printer automatically powers ON when connected to an active AC power source. Supports Sleep Mode and Power OFF with Sleep Mode Delayed features. When Power Failure Recovery Mode is initiated, the printer resets and and runs the Initial Power ON sequence on the loss of power (Power OFF / Shutdown). Power Failure Recovery Mode is available ONLY on printers with a printer connectivity module installed.
	2. STATUS Indicator — Primary status indicator for overall printer health and operational status. Also known as the Power indicator.	Green — The printer is ready to print and engage in data transfer. Green, slowly turning on and off — The printer is in sleep mode. Red — Media out, media detection error, head (cover/printhead) open, cut error, or printhead authentication failure. Amber — Printhead over temp (temperature), printhead element failure, out of memory while storing content (formats, graphics, fonts, etc.), and interface power fault for USB Host or serial ports. Blinking amber — Printhead under temp (temperature). Blinking red — Printhead over temp (temperature). This status is coupled with blinking red PAUSE indicator. Printer requires cooling and restart.
	3. PAUSE Indicator — The printer is in Pause mode when the Pause indicator light is on. A label (print form) or all labels (print forms) in the print buffer’s queue can be canceled using the CANCEL button when the Pause indicator is on.	Amber — Printer is paused. The print, label feed (advance), and other label routines are suspended until you exit the printer from Pause state by pressing PAUSE . Blinking red — Printhead over temp (temperature). Coupled with blinking red STATUS indicator, indicates that the printer must be allowed to cool and then restarted.
	4. DATA Indicator — Indicates the status of data transfer activity.	Off — Data transfer is not occurring. Green — A data communication operation has not finished, but data is not actively being transferred. Blinking green — Data communication in process. Blinking amber — OUT OF MEMORY while storing content (formats, graphics, fonts, etc.).
	5. SUPPLIES Indicator — Indicates status of media loaded in the printer (label, receipt, tags, transfer ribbon, ribbon cartridge, etc.)	Red — Media Out. Blinking red — RIBBON OUT. Applies to printing in Thermal Transfer mode. (The printer does NOT require ribbon to print in Direct Thermal mode.) Blinking red and amber — Ribbon Cartridge Low (ZD421 Ribbon Cartridge printers only). Blinking amber — RIBBON IN (ZD421 Ribbon Cartridge printers only). Detected when the printer is set to print in Direct Thermal mode, a mode in which the printer does NOT require ribbon to print.
	6. NETWORK Indicator — Indicates network activity and status.	Amber — 10 base Ethernet (LAN) connection detected. Green — 10/100 Ethernet (LAN) connection detected or when Wi-Fi (WLAN) has a strong signal and is connected. Red — when an Ethernet (LAN) or Wi-Fi (WLAN) fault occurs. Blinking red — during Wi-Fi (WLAN) association. Blinking amber — during Wi-Fi (WLAN) authentication. Blinking green — when a Wi-Fi (WLAN) connection has been established but the signal is weak.
	7. CANCEL Button — Cancels print jobs. Functional only when the printer is in Pause state.	Cancel printing — Press CANCEL one time to cancel printing the next format in the print buffer. Cancel all print jobs — Press and hold CANCEL for two seconds. The printer cancels printing ALL pending formats.
	8. FEED (Advance) Button — Advance a label (print form/format).	Feed one label (one blank form or format length of a label, receipt, tag, ticket, etc.) — Press and release FEED when the printer is not printing. Advance multiple labels — Press and hold FEED when the printer is not printing. The printer advances loaded media to the beginning position of the next label (format/form) and the next until you release FEED . Reprint last label (activated using a SGD command: ezpl.reprint_mode ) — This feature allows the reprinting a failed media print. If the printer runs out of media (paper, labels, transfer ribbon, etc.), it can reprint the last label (print form or format). The print buffer which stores the print image for printing and reprint is automatically cleared when the printer is turned off or reset.
	9. PAUSE Button — Pauses print and media movement actions.	Stop print activities and place the printer into Pause state — Press PAUSE . The printer finishes printing the current label before it pauses. The PAUSE indicator displays Amber (orange/yellow) to indicate the printer is in Pause state. Exit the printer out of Pause state and return it to normal operation — Press PAUSE when the printer is in Pause state. If you are printing a multi-label (form or format) job or if one or more other prints job are in the print queue, the printer resumes printing the job(s) in queue.

On printers with a Color Touch display, the user interface controls are mapped as shown here. The functionality of the buttons is the same as described earlier.

1	Status indicators	4	CANCEL button
2	PAUSE button	5	Color Touch display and interface
3	FEED button	6	POWER button