Datasheet

Section 8 Data Transfer Controller (DTC)
Rev.6.00 Mar. 18, 2009 Page 318 of 980
REJ09B0050-0600
2. Perform settings for transfer to the TPU’s TGR. Set MRA to source address incrementing
(SM1 = 1, SM0 = 0), fixed destination address (DM1 = DM0 = 0), normal mode (MD1 = MD0
= 0), and word size (Sz = 1). Set the data table start address in SAR, the TGRA address in
DAR, and the data table size in CRA. CRB can be set to any value.
3. Locate the TPU transfer register information consecutively after the NDR transfer register
information.
4. Set the start address of the NDR transfer register information to the DTC vector address.
5. Set the bit corresponding to TGIA in DTCER to 1.
6. Set TGRA as an output compare register (output disabled) with TIOR, and enable the TGIA
interrupt with TIER.
7. Set the initial output value in PODR, and the next output value in NDR. Set bits in DDR and
NDER for which output is to be performed to 1. Using PCR, select the TPU compare match to
be used as the output trigger.
8. Set the CST bit in TSTR to 1, and start the TCNT count operation.
9. Each time a TGRA compare match occurs, the next output value is transferred to NDR and the
set value of the next output trigger period is transferred to TGRA. The activation source TGFA
flag is cleared.
10. When the specified number of transfers are completed (the TPU transfer CRA value is 0), the
TGFA flag is held at 1, the DTCE bit is cleared to 0, and a TGIA interrupt request is sent to the
CPU. Termination processing should be performed in the interrupt handling routine.
8.7.3 Chain Transfer when Counter = 0
By executing a second data transfer, and performing re-setting of the first data transfer, only when
the counter value is 0, it is possible to perform 256 or more repeat transfers.
An example is shown in which a 128-kbyte input buffer is configured. The input buffer is assumed
to have been set to start at lower address H'0000. Figure 8.13 shows the chain transfer when the
counter value is 0.
1. For the first transfer, set the normal mode for input data. Set fixed transfer source address
(G/A, etc.), CRA = H'0000 (65,536 times), and CHNE = 1, CHNS = 1, and DISEL = 0.
2. Prepare the upper 8-bit addresses of the start addresses for each of the 65,536 transfer start
addresses for the first data transfer in a separate area (in ROM, etc.). For example, if the input
buffer comprises H'200000 to H'21FFFF, prepare H'21 and H'20.
3. For the second transfer, set repeat mode (with the source side as the repeat area) for re-setting
the transfer destination address for the first data transfer. Use the upper 8 bits of DAR in the
first register information area as the transfer destination. Set CHNE = DISEL = 0. If the above
input buffer is specified as H'200000 to H'21FFFF, set the transfer counter to 2.