KluPhi

Hello, I have been experimenting with the External Hardware → MCDU Export feature in the iniBuilds A300 in order to drive an external MCDU display via SimConnect. In general the export works well and the screen contents can be reconstructed quite reliably. However, while implementing a renderer I noticed a few behaviours where the exported data does not seem to match the cockpit display exactly. I wanted to ask if someone from the iniBuilds team could clarify how the export is intended to behave. Observations From testing multiple pages it appears that the exported screen data follows a fixed grid layout with rows and columns plus additional formatting information per cell. This works correctly for most pages. However, there are some cases where the output differs slightly from what is shown on the cockpit MCDU. 1. Formatting / separator lines On some pages (for example PROG) certain separator or formatting lines appear slightly different in the exported data compared to the cockpit display. The overall structure is correct, but spacing or special characters do not always match exactly. This made me wonder if the cockpit renderer internally uses additional layout logic that is not fully represented in the export grid. 2. Visible character width Visually on the cockpit MCDU, some lines appear to contain more characters than the exported grid suggests, particularly: the scratchpad some separator/status lines However the exported data still seems to follow the same fixed grid width. This suggests that the cockpit renderer might apply slightly different spacing or glyph rendering compared to the logical grid used in the export. 3. Possible row order inconsistency on the F-PLN page While debugging the F-PLN page I also noticed something that looks like a row order mismatch. It appears that: the first row of the screen does not appear where expected in the exported data another row from near the bottom of the display appears in that position instead The remaining rows seem to match the visual order correctly. This may of course be related to how the page is internally structured, but it made me wonder whether some rows are handled differently in the export. Questions To better understand how the export is intended to be used, I would mainly be interested in the following: Is the exported MCDU screen strictly based on a fixed grid layout, or does the cockpit renderer apply additional formatting logic that is not included in the export? What exactly does the formatting flag per cell represent? Are there any page-specific behaviours (for example on the F-PLN page) where the exported row order may differ from the visual cockpit display? The export feature is already very useful and works well for most pages. Understanding the intended structure of the data a bit better would make it much easier to reproduce the display accurately on external hardware. Any clarification from the iniBuilds team would be greatly appreciated. Thanks!