Configuring SINUMERIK Operate Easy Screen Program Selection on 828D/840D

1. Problem Overview

Operators on shop-floor SINUMERIK 828D and SINUMERIK 840D sl controllers frequently need to switch between a small set of recurring part programs (.MPF files) without navigating through the full directory tree, part program manager, or HMI soft-key hierarchy. The shipped Easy Screen runtime includes only a single-program launch behavior, so a custom dialog must be built that:

• Displays a numbered list of named part programs.
• Allows the operator to scroll and pick a single entry.
• Loads the corresponding .MPF from a workplan directory (.WPD).
• Optionally starts execution immediately.

Easy Screen provides no native program-list widget, so the dialog must be constructed from the supported primitives: a DEF TXT indirect text variable, vertical soft-keys (VS) for navigation, and horizontal soft-keys (HS) for commit actions. The SP() function is used to load the selected program.

2. Prerequisites

Verify access level before editing: Setup → Password → enter Manufacturer password. The CF card must be write-enabled in the NCU's Setting screen or via scard command in the service menu.

3. Easy Screen Architecture

Easy Screen files are plain-text definitions with the extension .eas (compiled) or .com (source). The runtime parses them on power-up if they reside in the configured template path. Three constructs are used in the program-selection pattern:

4. Step 1: Define the Indirect Text Variable

The DEF TXT statement binds a numeric NC variable to an indexed string table. The runtime inspects the variable and shows the matching entry. The syntax is:

DEF TXT<id>=(i/* <ncvar>=<v0>="string0",<v1>="string1",... <vn>="stringN" //
            ,/<default>//"<fallback>"/,,/<X>,<Y>,<W>,/<attr>,<type>)

For a three-program picker driven by $R[267]:

DEF TXT1=(i/* 0="Test Program 1",1="Test Program 2",2="Test Program 3" //,
          ,,"/wr1//"$R[267]"/,,/185,40,200,/0,2)

Parameter breakdown:

Any integer NC variable may be used. GUD (Global User Data) variables such as GUD_1[0] are also valid and recommended for production to avoid clashes with reserved R-numbers. Keep R-numbers below 100 reserved for Siemens defaults; use 200+ for application logic.

5. Step 2: Configure a Vertical Soft-Key for Selection

Vertical soft-keys live on the right side of the screen and let the operator increment/decrement the linked variable. The declaration uses VS<id>=("label%nstep") where %n inserts a newline and step is the delta applied to the variable when the key is pressed.

VS1=("Program%n1")
PRESS(VS1)
    TXT1.val=0
    LM("PROG")
END_PRESS

Behavior:

1. Operator touches VS1 on the right edge of the screen.
2. Runtime executes the PRESS(VS1) block.
3. TXT1.val=0 resets the indirect text index to 0 (so the picker starts clean).
4. LM("PROG") loads the Easy Screen file PROG.eas from the template path.

6. Step 3: Configure the Horizontal Soft-Key for Commit

Horizontal soft-keys appear on the bottom bar (8 keys max). The commit key inspects the current value of the indirect variable and dispatches the matching program via SP():

HS1=("Start%nProgram")
PRESS(HS1)
    IF TXT1==0
        SP("\WKS.DIR\PROG.WPD\PROG1.MPF")
        EXIT
    ELSE
        IF TXT1==1
            SP("\WKS.DIR\PROG.WPD\PROG2.MPF")
            EXIT
        ELSE
            IF TXT1==2
                SP("\WKS.DIR\PROG.WPD\PROG3.MPF")
                EXIT
            ENDIF
        ENDIF
    ENDIF
END_PRESS

Each branch terminates with EXIT so the runtime does not fall through to the next test. This pattern is the only practical way to bind a discrete list to a hard-coded path in Easy Screen; there is no array or loop construct in the language.

7. Step 4: File-System Layout

The SP() function takes a fully qualified NCK path. On 828D and 840D sl, programs live under /WKS.DIR/<workplan>.WPD/<program>.MPF. The Windows-style backslashes are required by the path interpreter:

To create the workplan directory from the operator panel: Program Manager → WKS.DIR → New Directory → name = PROG. Copy or paste your .MPF files into it. The path is case-sensitive on NCU firmware ≥ V4.8.

8. Step 5: The Full Screen Source

The complete file /siemens/sinumerik/hmi/template/easyScreen/PROG.eas for a three-program picker:

;--------------------------------------------------------------
; SINUMERIK Operate Easy Screen - Program Selector
; Compatible with 828D and 840D sl, HMI V4.5 SP2 or later
; Author: shop-floor template
;--------------------------------------------------------------

DEF TXT1=(i/* 0="Test Program 1",1="Test Program 2",2="Test Program 3" //,
          ,,"/wr1//"$R[267]"/,,/185,40,200,/0,2)

VS1=("Program%n1")
PRESS(VS1)
    TXT1.val=0
    LM("PROG")
END_PRESS

HS1=("Start%nProgram")
PRESS(HS1)
    IF TXT1==0
        SP("\WKS.DIR\PROG.WPD\PROG1.MPF")
        EXIT
    ELSE
        IF TXT1==1
            SP("\WKS.DIR\PROG.WPD\PROG2.MPF")
            EXIT
        ELSE
            IF TXT1==2
                SP("\WKS.DIR\PROG.WPD\PROG3.MPF")
                EXIT
            ENDIF
        ENDIF
    ENDIF
END_PRESS

HS8=("Back")
PRESS(HS8)
    EXIT
END_PRESS

Save the file to the CF card, restart HMI (or use Setup → HMI → Reload), then navigate to the Easy Screen via the operating-area switch key.

9. Extending to More Than Three Programs

For an N-entry picker, declare each entry as a separate DEF TXT on the same canvas with offset Y coordinates, or stack them in a single column by adjusting the 40 pixel base offset in 24-pixel increments. The PRESS block must contain a corresponding IF / ELSE IF chain. Example for five programs:

HS1=("Start%nProgram")
PRESS(HS1)
    IF TXT1==0
        SP("\WKS.DIR\PROG.WPD\PROG1.MPF")
    ELSE
        IF TXT1==1
            SP("\WKS.DIR\PROG.WPD\PROG2.MPF")
        ELSE
            IF TXT1==2
                SP("\WKS.DIR\PROG.WPD\PROG3.MPF")
            ELSE
                IF TXT1==3
                    SP("\WKS.DIR\PROG.WPD\PROG4.MPF")
                ELSE
                    IF TXT1==4
                        SP("\WKS.DIR\PROG.WPD\PROG5.MPF")
                    ENDIF
                ENDIF
            ENDIF
        ENDIF
    ENDIF
    EXIT
END_PRESS

For more than 10 programs, switch from a manual IF tree to a PLC-driven program selection (next section) which scales linearly without source bloat.

10. PLC Program-Selection Alternative

For installations where the operator screen is built on the PLC rather than Easy Screen, Siemens provides program selection from the PLC. The PLC writes a job number into the NCK interface, the NCK fetches the matching program from SPF_DIR, and reports back the active program. The relevant interface is the PI service SELECT (PI index 0x05 / 5) accessed via FB9 or FB11 in the Siemens PLC toolbox.

Triggering from the PLC avoids the per-entry IF chain entirely and is the recommended path when the picker exceeds roughly ten entries or when programs must be selected based on a barcode scan or production order number.

11. Reference: Soft-Key Limits and Naming

Soft-key labels may contain up to two lines, separated by %n. Special characters %, ",\ must be escaped with a leading \.

12. Reference: SP() Function Semantics

13. Reference: LM() Screen Loading

LM("name") loads the Easy Screen file name.eas from the active template directory. The name is case-insensitive on HMI < V4.7 and case-sensitive on HMI ≥ V4.7. To chain screens without recursion, use EXIT to leave the current PRESS block before calling LM() if the target screen is the same one (loop); otherwise LM() replaces the visible screen immediately.

14. Commissioning Procedure

1. Insert a USB or CF card with the new PROG.eas file.
2. From the operator panel, navigate to Setup → Password and enter the Manufacturer password.
3. Open Start-up → HMI → Explorer (or use WinSCP / PuTTY against the NCU at port 22 / 23).
4. Copy PROG.eas to /siemens/sinumerik/hmi/template/easyScreen/.
5. Power-cycle the HMI or select Setup → HMI → Reload Easy Screen.
6. Switch to the operating area where Easy Screen is exposed (typically a custom area; activate it under Setup → Operating Areas).
7. Touch VS1: confirm the screen re-displays with PROG1 highlighted.
8. Touch HS1: confirm the active program in the NC block display switches to PROG1.MPF.
9. Press NC Start: confirm the program executes.

15. Verification Checklist

16. Troubleshooting Matrix

17. Safety Notes

18. Related Constructs and Edge Cases

Dynamic index via arithmetic: The TXT1.val property accepts expressions, so you can drive the picker from a calculation. Example: TXT1.val = $AA_IM[X] / 100 binds the picker to an analog input scaled to the integer index.

Reading vs writing: Replace i (input) with o (output-only) on the DEF line if the index must be display-only and not user-editable.

Multi-channel systems: On 840D sl with multiple channels, use SP("\WKS.DIR\PROG.WPD\PROG1.MPF",1) with a second argument indicating the channel number when the picker is invoked from a non-default channel.

Localization: The string table accepts Unicode on HMI ≥ V4.7. Use UTF-8 encoded source files and the /utf8 directive in the .eas header.

19. Frequently Asked Questions