Addressing Mode - Fujitsu FR60 Hardware Manual

16.3.5

Addressing Mode

Specify the transfer destination/transfer source address independently for each transfer
channel.
This section describes the specification method. Specify the addresses based on the
transfer sequence.
■ Address Register Specifications
In 2-cycle transfer mode, set the transfer source address in the transfer source address setting register
(DMASA) and the transfer destination address in the transfer destination address setting register
(DMADA).
In fly-by transfer mode, specify the memory address in the transfer source address setting register
(DMASA). In this case, the value in the transfer destination address setting register (DMADA) is ignored.
[Features of the Address Register]
• This register has the maximum 32-bit length. With 32-bit length, all space in the memory map can be
accessed.
[Function of the Address Register]
• The address register is read in each access operation and the read value is sent to the address bus.
• At the same time, the address for the next access is calculated by the address counter and the address
register is updated using the calculated address.
• For address calculation, increment or decrement is selected independently for each channel, transfer
destination, and transfer source. The address increment/decrement width is specified by the address
count size register (SASZ/DASZ of DMACB).
• If reloading is not enabled, the address resulting from the address calculation of the last address remains
in the address register when the transfer ends.
• If reloading is enabled, the initial value of the address is reloaded.
Note:
If an overflow or underflow occurs as a result of 32-bit length full address calculation, an address
error is detected and transfer on the relevant channel is stopped. (Refer to the description for the
items related to the end code).
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