7721 datasheet(355/577 Pages) RENESAS

355 / 577 page

DMA CONTROLLER

13-76

13.7 Array chain transfer mode

7721 Group User’s Manual

Fig. 13.7.6 Operation flowchart of array chain transfer mode

Burst·Level·H

Cycle-steal·No request

Note: When TC pin validity bit is “1”

First of 1 block ?

SARi

← Transfer parameter (Note)

(Transfer source’s transfer start address)

DARi

← Transfer parameter (Note)

(Transfer destination’s transfer start address)

TCRi

← Transfer parameter

(Byte number of transfer data)

TCRi latch

← TCRi latch – 1

First

On and after

second

Transfer

completion of all blocks ?

TCRi latch = 0 ?

Y. Completion

DMAi request bit

← 0

1-unit transfer

Transfer completion

of 1 block ?

(Only in cycle-steal transfer mode)

(Refer to section “13.4 Operation.”)

TC “L” output (Note)

DMAi interrupt request bit

← 1

DMAi enable bit

← 0

DMAi request bit

← 0

(Only in burst transfer mode (edge sense))

DMAi request bit ?

Burst·Level·H

Cycle-steal·No request

Burst·Edge

: In burst transfer mode (edge sense)

Burst·Level·L

: In burst transfer mode (level sense) with DMAREQi pin = L

Burst·Level·H

: In burst transfer mode (level sense) with DMAREQi pin = H

Cycle-steal·Requested

: In cycle-steal transfer mode with any request of DMA0–3

Cycle-steal·No request

: In cycle-steal transfer mode with no request of DMA0–3

SARi latch indicates the start address of the transfer parameter memory of the next block.

TCRi latch indicates the number of remaining transfer blocks.

Note: The above figure applies when 2-bus cycle transfer is performed.

When data is transferred from memory to I/O in 1-bus cycle transfer, there is no “DARi

← Transfer parameter.”

When data is transferred from I/O to memory in 1-bus cycle transfer, there is no “SARi

← Transfer parameter.”

Burst•Edge

Burst·Level·L

Cycle-steal·Requested

DMAi request bit ?

Burst·Edge

Burst·Level·L

Cycle-steal·Requested

7721 Datasheet(PDF) 355 Page - Renesas Technology Corp

7721 Datasheet(HTML) 355 Page - Renesas Technology Corp

Html Pages

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 ...More

Datasheet Download

Link URL