Toshiba H1 Series - Manual (Page 498)

TMP92CZ26A
92CZ26A-495
• Note of FIFO buffer
There are following notes in this SPIC.
1) Transmit
Data is overwritten if write data with condition transmit FIFO buffer is FULL.
Interrupt and transmission are not executed normally because write-pointer in FIFO
becomes abnormal condition. Therefore, manage number of writing by using software.
If transmit is sequential, writing the data to transmit FIFO every 16 bytes is always
needed. If writing other than 16 bytes, TEMP interrupt does not generate normally.
Note: If transmitting it by except 16 byte, use UNIT transmitting.
2) Receive
If read data with condition receive FIFO is empty, undefined data is read. Interrupt
and receiving are not executed normally because read-pointer in FIFO becomes
abnormal condition. Therefore, manage number of reading by using software.
If receive is sequential, reading the data from receive FIFO every 16 bytes is always
needed. If reading other than 16 bytes, RFUL interrupt does not generate normally.
Note: If transmitting it by except 16 byte, use UNIT receiving.
3) CRC
CRC is generated in I/O point. Please take care soft ware process to compare the CRC when used FIFO.
Ex. Sequential receive
1. Start sequential receive
2. finish valid data receive (FIFO_Full)
3. disable receive
4. valid data read from FIFO to temporary buffer(internal RAM)
5. CRC1 read from CRC generator in SPI circuit
6. CRC2 receive (enable UNIT receive from SD-CARD)
7. compare CRC1 and CRC2
Note: Above 2 to 4 process can be used DMAC, however it must stop sequential receive (process 3)
before to get CRC2 form SD-CARD.