2 - Principles of operation—Using the PODs2–22.3 Using the PODsA POD consists of a continuous rotary encoder or“knob”, with two keys (or “switches”) under it. Thereare four PODs located directly under the displayscreen.The knob is used to set continuously variable param-eters shown on the screen (for example, the amountof signal sent to an Aux buss), while the switches areused for “on/off”-type screen parameters (e.g. pre-orpost-fader send).A typical screen showing POD use is shown below(the method of actually selecting screens is givenbelow):The controls on the screen are shown in rows, eachrow corresponding to the four PODs.The heavy blinking box surrounding a row shows thecurrently-active row. Turning a POD knob will havethe effect of changing the corresponding parameterin the active row (turning the left POD knob willadjust the left parameter in the active row, etc.).In the example above, the right on-screen control inthe active row is “grayed out”. This means that thecorresponding POD has no function when this row isactive.Note that PODs which are enabled, but not in the cur-rently active row, are shown as small dashed circles.PODs which are disabled, and not in the currentlyactive row, are shown as small gray circles.Where both switches of a POD are unused, they arenot displayed on screen. When only one switch of aPOD is used, the other is “grayed out”.To change the active row, use the ROW CURSORkeys to the right of the PODs to move the heavyblinking box indicating the active row.In addition to the POD knobs, the POD switches canalso be used in a number of cases in this screen to setvarious parameters.In this way, comparatively few physical controls canbe made to adjust many parameters. Since these con-trols are centralized, this allows for very efficientworking with the TM-D4000.2.3.1 Selecting screensDisplay screens are selected using the group of keysto the left of the display screen.Sometimes a key will have two labels, one above andone below. The function described by the lower labelis accessed by pressing the SHIFT key so that theSHIFT indicator lights, and then pressing the appro-priate key.The screen shown below is a DIGITAL I/Oscreen, as shown by the title in the top right corner ofthe screen. Accordingly, the (unshifted) key whoseupper label is DIGITAL I/O should be pressed.Note that this screen contains three “tabs” under thetitle. This is because there are more parameterswhich fall under the heading of “digital I/O” than canfit on one screen.Currently, the I/O SETUP tab is at the top, andit is these parameters which are available for editing.To change to the next tab, CLOCK, press theDIGITAL I/O key once more (with the SHIFT indica-tor lit).Another press of the DIGITAL I/O key will bring theCASCADE tab to the front, and pressing it one