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HD6432351 Datasheet, PDF (277/989 Pages) Renesas Technology Corp – The H8S/2000 CPU has an internal 32-bit architecture, is provided with sixteen 16-bit general registers and a concise
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.
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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.
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