So let's play further:

Start with a program section as introduced above. Now you want to insert RCL 12 after step 0010. You put the program pointer to step 0010, which means this step will be in the center of the screen with the steps down to 0013 displayed (the steps 0007 - 9 are of no interest here):

Code: Select all

```
0010 arcsin
0011 |x|
0012 +
0013 MOD
```

Quickly press STO, and will see (almost) as you wanted and expect:

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```
0010 arcsin
0011 STO __
0012 |x|
0013 +
```

Rats! Wrong key! So press EXIT and get:

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```
0010 arcsin
0011 |x|
0012 +
0013 MOD
```

Press the right key now and get:

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```
0010 arcsin
0011 RCL __
0012 |x|
0013 +
```

Finish insertion with the register address:

Code: Select all

```
0010 arcsin
0011 RCL 12
0012 |x|
0013 +
0014 MOD
```

Now step 0011 is the current step and moves in the center. The procedure sketched here is what I called a 'vibrating display' in my post above, meaning there will be steps vanishing and popping up during insertion. Is this what you want? Just strive to understand your wishes.