Flyby Transfer - NEC V850E/MS1 UPD703100 User Manual

32-/16-bit single-chip microcontrollers

Table of Contents

6.6.2 Flyby transfer

The V850E/MS1 supports flyby transfer between external memory and external I/O, and internal RAM and internal

peripheral I/O.

(1) Flyby transfer between external memory and external I/O

This data transfer between memory and I/O is performed in one cycle. To achieve single-cycle transfer, the

memory address is always output irrespective of whether it is that of the source or the destination, and the

read/write strobe signals for the memory and I/O are made active at the same time.

The external I/O is selected with the DMAAK0 to DMAAK3 signal.

Figure 6-8 shows examples of flyby DMA transfer for an external device.

Figure 6-8. Timing of Flyby Transfer (DRAM → → → → External I/O) (1/3)

Internal DMA

request signal

Remarks 1. The circles indicate the sampling timing.

2. Broken lines indicate high impedance.

3. n = 0 to 3

CHAPTER 6 DMA FUNCTIONS (DMA CONTROLLER)

(a) Block transfer mode

User's Manual U12688EJ4V0UM00

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