GigaDevice Semiconductor GD32 Series, User Manual

Page: 55 / 65

AN050
GD32 USBFS&USBHS Firmware Library User Guide
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} else if ( PIPE_PERIOD == pp_mode ) {
txfiforeg = & udev -> regs . hr -> HPTFQSTAT ;
} else {
return 0U ;
}
txfifostate = * txfiforeg ;
pp_num = ( uint8_t )(( txfifostate & TFQSTAT_CNUM ) >> 27U );
word_count = ( uint16_t )( udev -> host . pipe [ pp_num ]. xfer_len + 3U ) / 4U ;
while ((( txfifostate & TFQSTAT_TXFS ) >= word_count ) && ( 0U !=
udev -> host . pipe [ pp_num ]. xfer_len )) {
len = ( uint16_t )( txfifostate & TFQSTAT_TXFS ) * 4U ;
if ( len > udev -> host . pipe [ pp_num ]. xfer_len ) {
/* last packet */
len = ( uint16_t ) udev -> host . pipe [ pp_num ]. xfer_len ;
if ( PIPE_NON_PERIOD == pp_mode ) {
udev -> regs . gr -> GINTEN &= ~ GINTEN_NPTXFEIE ;
} else {
udev -> regs . gr -> GINTEN &= ~ GINTEN_PTXFEIE ;
}
}
word_count = ( uint16_t )(( udev -> host . pipe [ pp_num ]. xfer_len + 3U ) / 4U );
usb_txfifo_write (& udev -> regs , udev -> host . pipe [ pp_num ]. xfer_buf , pp_num , len ); // write
FIFO
udev -> host . pipe [ pp_num ]. xfer_buf += len ;
udev -> host . pipe [ pp_num ]. xfer_len -= len ;
udev -> host . pipe [ pp_num ]. xfer_count += len ;
txfifostate = * txfiforeg ;
}
return 1U ;
}