NTSC mode and serial port?

bbond007 · **Joined:** Tue Nov 10, 2009 11:56 pm **Posts:** 43

I have been using my Minimig with a bluetooth serial adapter clocked at 115200 BPS. With NCOMM 3.06 when I'm in NTSC mode the serial port does not work(just get junk if anything). In PAL mode it works perfectly.

I also tried with Term 4.8 and Termite and they do the same.

I don't know if it effects all BPS rates. Its real hard for me to try different BPS rates (right now) because the utility to configure the bluetooth adapter requires windows and the USB serial adapter I need to use to do that not have signed windows drivers and I think the reason why is because the drivers are buggy.

Is this a bug?

oh, I also tried booting in NTSC and changing to PAL screen mode. Still does not work.

I'll pick up a new USB serial port that has Windows7 drivers and try different BPS rates.

Thanks

nate

boing4000 · **Posted:** Thu Jan 05, 2012 2:12 pm

There could be a timing adaption between NTSC and PAL mode in real CIA chip.
After all one CIA trigger at v-sync signal and may act differently in 50 or 60Hz mode.
I wil take a look at this asap.

bbond007 · **Joined:** Tue Nov 10, 2009 11:56 pm **Posts:** 43

boing4000 wrote:

There could be a timing adaption between NTSC and PAL mode in real CIA chip.
After all one CIA trigger at v-sync signal and may act differently in 50 or 60Hz mode.
I wil take a look at this asap.

No big deal

I typically leave it in PAL mode anyway.

The serial just stopped working one day and it took me a while to figure out what was going on

If I manage to get to the Tiger Direct store on my lunch I'll get the new USB serial adapter and then I can try to set the bluetooth thing for different BPS rates to see if only 115200 is effected.

thanks!

nate

boing4000 · **Posted:** Thu Jan 05, 2012 5:14 pm

Rememer the 115200 bps is only useable in Turbo mode. Else the 68000 is too slow to handle the RS232 protocol speed.
In Normal mode a maximum of ca. 19200 bps could work without many bit error/retry loop.

MMrobinsonb5 · **Joined:** Tue Dec 13, 2011 7:48 pm **Posts:** 241

boing4000 wrote:

There could be a timing adaption between NTSC and PAL mode in real CIA chip.
After all one CIA trigger at v-sync signal and may act differently in 50 or 60Hz mode.
I wil take a look at this asap.

Could also be the serial period in Paula - it's calculated differently between NTSC and PAL machines.
If either the OS is misidentifying the machine as PAL instead of NTSC, or the Minimig's claiming to be NTSC but still using a PAL base clock, that could cause it.

bbond007 · **Joined:** Tue Nov 10, 2009 11:56 pm **Posts:** 43

boing4000 wrote:

Rememer the 115200 bps is only useable in Turbo mode. Else the 68000 is too slow to handle the RS232 protocol speed.
In Normal mode a maximum of ca. 19200 bps could work without many bit error/retry loop.

yes, I was doing a large zmodem transfer and switched out of turbo mode just to see what would happen...

it started to go downhill real quickly.

I forgot to mention that I also tried both 8n1.device and serial.device and both have the same NTSC issue.

thanks!

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NTSC mode and serial port?

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