Brainboxes CC-662 Hardware Manual page 32

PCI Photon 8 Port RS232
Card's 128 byte FIFO are 1, 32, 64 and 112.
Transmit Buffer - These settings allow the selection of a
transmitter FIFO trigger setting. Selecting a low value will
send fewer data-bytes per interrupt, and this is
recommended if you are communicating to a slower
machine. Selecting a high value will send more data-bytes
per interrupt, and will give more time for multi-tasking
operations. The trigger options in the case of the Photon
Card's 128 byte FIFO are 1, 32, 64 and 112.
2. Restore-
Clicking on this port will restore the port setting
of the Serial Solutions tab to the values set on entry to this
page.
Software Installation
Chapter 3 Page 32