Resolution for galdrvr.c

I'm modelling resolution for galdrvr.c driver. This is bit tricky because horizontal should be 768 why vertical only 224 (I've calculated 240 because my TV won't handle 224 correctly) and with 60,606061 Hz. I've calculated following modeline:

Horizontal
Active: 768
Total: 1052
Start: 862
End: 957

Vertical
Active: 240
Total: 261
Start: 242
End: 245

Pixel clock: 1052 x 261 x 60,606061 = 16,6407

is this modeline should work on TV? I've tested similiar resolution taken from web but but upon starting Super Cobra my TV started emiting some high pitch so I stopped test and didn't try again, probably won't hurt my TV but who knows.

My TV is Sony 29'' flat CRT.

Is there any other way to run these games on old resolution 256x224 (256x240)? Is it possible to move it to galaxold.c or use graphics stretching without and tearing or visible signs resizing?

EDIT. ok, I've menaged to run those games as desired (in window 320x240) in cabmame. Still no success in official mame.

That resolution should be no problem for your TV. TVs don't care about pixels anyway :) Just Lines.

Ok, I'll try, thanks for reply.

Ok, I've made it but with partial success.

I used modeline "768x240 60,61" 16,6441 768 847 941 1052 240 241 243 261 -hsync -vsync

It's slighty moved to the right because my TV always cuts some lines from the top and from the left. In fact most of resolutions I have are cropped like this, why?

Other problem is perfect timing. No mather what I put in pixel clock Super Cobra always has some stuttering. I tried clock 16,640 (manually calculated) then 16,6421 (taken from modeline editor) then I used Powerstrip to manually edit frequency but even with this changes stuttering is noticable. What I'm doing wrong?

Problem solved