Renesas SH7709S Stereo System User Manual


 
Rev. 5.00, 09/03, page 385 of 760
As a result, the values in the DMAC are as shown in table 11.10 when the fourth transfer ends,
depending on whether the address reload function is on or off.
Table 11.10 Values in DMAC after End of Fourth Transfer
Items Address reload on Address reload off
SAR H'04000080 H'04000090
DAR H'003FFFFC H'003FFFFC
DMATCR H'0000007C H'0000007C
Bus right Released Held
DMAC operation Stops Keeps operating
Interrupt Not generated Not generated
Transfer request source flag
clearing
Executed Not executed
Notes: 1. An interrupt is generated regardless of whether the address reload function is on or off,
if transfers are executed until the value in DMATCR reaches 0 and the IE bit in CHCR
has been set to 1.
2. The transfer request source flag is cleared regardless of whether the address reload
function is on or off, if transfers are executed until the value in DMATCR reaches 0.
3. Specify burst mode when using the address reload function. This function may not be
correctly executed in cycle-steal mode.
4. Set a multiple of four in DMATCR when using the address reload function. This function
may not be correctly executed if other values are specified.
11.5.3 Example of DMA Transfer between External Memory and SCIF Transmitter
(Indirect Address On)
In this example, DMA transfer is performed between the external memory specified by indirect
address (transfer source) and the SCIF transmitter (transfer destination) using DMAC channel 3.
Table 11.11 shows the transfer conditions and register settings. In addition, the trigger for the
number of transmit FIFO data bytes is set to 1 (TTRG1 = TTRG0 = 1 in SCFCR).