HD64F2357F20V Datasheet, PDF (249/1049 Pages) Renesas Technology Corp – Hardware Manual Renesas 16-Bit Single-chip Microcomputer H8S Family / H8S/2300 Series

Full Address Mode (Cycle Steal Mode): Figure 7-20 shows a transfer example in which TEND output is enabled and
word-size full address mode transfer (cycle steal mode) is performed from external 16-bit, 2-state access space to external
16-bit, 2-state access space.
ø
Address bus
RD
HWR
LWR
TEND
DMA
read
DMA
write
DMA
read
DMA
write
DMA
read
DMA DMA
write dead
Bus release
Bus release
Bus release Last transfer
cycle
Bus
release
Figure 7-20 Example of Full Address Mode (Cycle Steal) Transfer
A one-byte or one-word transfer is performed, and after the transfer the bus is released. While the bus is released one bus
cycle is inserted by the CPU or DTC.
In the transfer end cycle (the cycle in which the transfer counter reaches 0), a one-state DMA dead cycle is inserted after
the DMA write cycle.
Rev.6.00 Oct.28.2004 page 219 of 1016
REJ09B0138-0600H