Slow TWI single byte reads

[the_purple_pig]

I need to poll a NMEA data stream and it's easiest getting a byte at a time, but it's dropping to 30ms between individual reads in this loop:

uint8_t next = 0;
			uint8_t ref = 6;
			uint8_t readbuf[2] = {0};
			while(next != '\n')
			{
				nrf_gpio_pin_set(RED_LED);		
				if(twi_master_transfer(PAM7Q_ADDRESS | TWI_READ_BIT, readbuf, 1, TWI_DONT_ISSUE_STOP))
				{
					next = readbuf[0];
					if((next != 0xFF))
					{
						ubxMsg.B[ref] = next;
						ref++;
					}
				}
				nrf_gpio_pin_clear(RED_LED);
			}
			twi_master_transfer(PAM7Q_ADDRESS | TWI_READ_BIT, NULL, 1, TWI_ISSUE_STOP);

Is there anything I am doing blatantly wrong?

[MartinBL]

Hi. I can't see any obvious errors. Could it be your NMEA device that is slow? Are you able to measure where in your code your device is pausing?