fx2lp slave bulk in transfer, FLAGA stuck high, not able to reset

[vpac]

hello world,

im having a dvb tuner streaming over fx2lp slave IN to PC application.

when changing tv-channels the fx2lp gets a "hickup" not sending more data to PC.

i am monitoring the EP2STAT reg for EPfull and the EPprogrammable flags.

The FLAGA is output to a Pin CTL0 and toggles nicly when streaming.

Changing channel or turn off streaming gets FLAGA stay high (telling fifo full) and the EPfull bit also is on.

alright, i tryed to reset this situation by doing a FIFO-RESET sequence :

for (i=0;i<20;i++)
{
FIFORESET = 0x80; // activate NAK-ALL to avoid race conditions. ie. NAK all transfers
SYNCDELAY; // see TRM section 15.14

EP2CFG = 0x00; //switching to manual mode
SYNCDELAY;

FIFORESET = 0x82; // reset, FIFO 2
SYNCDELAY; //
FIFORESET = 0x82; // reset, FIFO 2
SYNCDELAY; //

EP2CFG = 0xE0; //switching back to auto mode
SYNCDELAY;

FIFORESET = 0x00; // deactivate NAK-ALL, resume normal operation
SYNCDELAY;
}

No chance, the FLAGA and th efull flag stay on, even when tuner is not streaming any more.

this is a beast 😉

[Rashi_Vatsa · Accepted solution]

Hello,

Please confirm if you are using the default firmware with this application note https://www.cypress.com/documentation/application-notes/an61345-designing-ez-usb-fx2lp-slave-fifo-in... .

If no, please let us know how is the changing of channel or streaming turned off handled by the firmware

[vpac]

i am using the " AN58069 - IMPLEMENTING AN 8-BIT PARALLEL MPEG2-TS INTERFACE USING SLAVE FIFO MODE IN FX2LP"

When i start a TV channel, everything works fine, the FLAGA (telling fifo half full) is toggling nicly.

When i stop the TV channel, the tuner is instructed to stop streaming the mpeg-stream and the mpeg-VALID signal on SLWR goes low, so there is no more input into the fifo.

However, FLAGA stays high, indicating fifo is above half-full, probably because the PC is not reading anymore.

So in this situation i want to reset the FLAGA by doing a EP2 fiforeset.(code above)

But it stays high...?

The reason why i want to reset is, when i re-start the stream afterwards i am getting bad input data or no data at all.

The FLAGA will not toggle anymore, it just stays high. hmm?

[MallikaK_22]

Hi,

Apologies for the delay in the response.

Please let us know the following:

>> In which mode are you using the flags, indexed or fixed?

>> How have you configured the endpoints?

>> What is the polarity of the flags?

It will be better if you can provide the firmware source,

Regards,

Mallika