Toshiba H1 Series Data Book page 490

Difference points between UNIT receive and Sequential receive
UNIT receive is the mode that receiving only 1 UNIT data. UNIT receive mode can be
selected by writing SPICT<RXMOD>= "0".
The receive FIFO is invalid in the UNIT receive mode. By writing SPICT<RXE>= "1",
receives 1UNIT data, loads received data in receive data register (SPIRD) and then stop
receiving. Reading (SPIRD) register should be executed after writing SPICT<RXE>= "0". If
reading (SPIRD) register with the condition SPICT<RXE>= "1" 1 UNIT data is received again.
During receiving, it is prohibited to change;
Sequential receive → UNIT receive
UNIT receive → Sequential receive
RFUL and REND interrupts generate when UNIT receiving is finished.
Sequential receive is the mode that receiving the data sequentially and automatically when
receive FIFO has space. Sequential receive is selected by writing SPICT<RXMOD>= "1".
The 32 bytes size of receive FIFO becomes valid in sequential receive mode. Reading the data
in receive FIFO every 16 bytes is always needed. If reading other than 16 bytes, RFUL
interrupt does not generate normally.
Received data is loaded to receive FIFO by writing SPICT<RXE>= "1".
Receiving next data is kept automatically unless data receive FIFO becomes full (32bytes).
Therefore receiving is not stopped every UNIT but kept sequentially. During receiving, it is
prohibited to change receiving mode;
If writing SPICT<RXE>= "0" during receiving, receiving is stopped after finishing to receive
the UNIT data in receiving.
RFUL interrupt generates when 16 and 32 bytes of the data is loaded to the FIFO. REND
interrupt generates when receiving 32 bytes size of the data is finished.
92CZ26A-487
TMP92CZ26A