Section 16 Serial I/O (SIO)
Rev. 2.00 Mar 09, 2006 page 679 of 906
REJ09B0292-0200
16.4
SIO Interrupt Sources and DMAC
Each SIO channel has four interrupt sources: the receive-overrun-error interrupt (RERI) request,
transmit-underrun-error interrupt (TERI) request, receive-data-full interrupt (RDFI) request, and
transmit-data-empty interrupt (TDEI) request. Table 16.3 shows the interrupt sources and their
relative priorities. The RDFI and TDEI interrupts are enabled by the RIE and TIE bits,
respectively, in SICTR. The RERI and TERI interrupts cannot be disabled.
An RDFI interrupt request is generated when the RDRF bit is set to 1 in SISTR. RDFI can activate
the DMA controller (DMAC) to read the data in SIRDR. RDRF is cleared to 0 automatically when
the DMAC reads data from SIRDR.
A TDEI interrupt request is generated when the TDRE bit is set to 1 in SISTR. TDEI can activate
the DMAC to write the next data to SITDR. TDRE is cleared to 0 automatically when the DMAC
writes data to SITDR.
When TDEI and RDFI interrupt requests are handled by the DMAC, and not by the interrupt
controller, a low priority level should be given to interrupts from the SIO to prevent the interrupt
controller from operating.
When the RERR bit is set to 1 in SISTR, an RERI interrupt request is generated.
When the TERR bit is set to 1 in SISTR, a TERI interrupt request is generated.
Channel interrupt priority levels are set by means of the IRPE register, as described in section 5,
Interrupt Controller (INTC).
Table 16.3 SIO Interrupt Sources
Interrupt Source
Description
DMAC Activation
Priority
RERI
Receive overrun error (RERR)
Not possible
High
TERI
Transmit underrun error (TERR)
Not possible
↑
RDFI
Receive data register full (RDRF)
Possible
↓
TDEI
Transmit data register empty (TDRE)
Possible
Low
Summary of Contents for SH7616
Page 10: ...Rev 2 00 Mar 09 2006 page x of xxvi ...
Page 132: ...Section 2 CPU Rev 2 00 Mar 09 2006 page 106 of 906 REJ09B0292 0200 ...
Page 568: ...Section 12 16 Bit Free Running Timer FRT Rev 2 00 Mar 09 2006 page 542 of 906 REJ09B0292 0200 ...
Page 582: ...Section 13 Watchdog Timer WDT Rev 2 00 Mar 09 2006 page 556 of 906 REJ09B0292 0200 ...
Page 706: ...Section 16 Serial I O SIO Rev 2 00 Mar 09 2006 page 680 of 906 REJ09B0292 0200 ...
Page 820: ...Section 19 Pin Function Controller PFC Rev 2 00 Mar 09 2006 page 794 of 906 REJ09B0292 0200 ...
Page 932: ...Appendix D Package Dimensions Rev 2 00 Mar 09 2006 page 906 of 906 REJ09B0292 0200 ...
Page 935: ...SH7616 Hardware Manual ...