TMPR3916 datasheet(116/225 Pages) TOSHIBA

116 / 225 page

Chapter 6 Direct Memory Access Controller (DMAC)

Preliminary

6-3

memory >> device: Write the value 0xA9 into the Operation Definition Register (ODR).

device >> memory:

Write the value 0x69 into the Operation Definition Register (ODR).

Write the value 0x11 into the Channel Control Register (CCR).

Now the DMA Controller waits for a request of the external device to start the first transfer.

Configure and start the devices TXSEI or UART.

After DMA transaction has finished, the DMA Controller sets the OPC bit (bit 0) in the Channel

Status Register (CSR) and generates an interrupt. Each channel has its own interrupt signal. The

interrupts are only maskable in the Interrupt Controller.

To terminate a running DMA transaction, set bit 22 (ABT) in the Channel Control Register (CCR).

6.1.2

Start DMA with External Device

The TMPR3916 has one pin for an external DMA request signal. For instance the external request

makes sense together with a PORT module. The procedure is similar to a UART/ TXSEI transaction.

For details of the procedure see section “Start DMA transaction between memory and TXSEI/UART”

and the register description.

The following steps are executed to start a DMA transaction:

Write the hexadecimal-value 0xA in

•

bits [3:0] of the Chip Configuration Register (CCR) for channel 0

•

bits [7:4] of the Chip Configuration Register (CCR) for channel 1

Define source and destination address in registers SAR and DAR.

Write the number of bytes you want to transfer into BCR.

Write the following value into ODR:

Application

Memory >> Device

(transmit)

Device >> Memory

(receive)

Edge detection on external request

0xA8

0x68

Level detection on external request

0xA9

0x69

Write the following value into CCR:

Application

Memory >> Device

(transmit)

Device >> Memory

(receive)

Positive logic on external request

0x19

Negative logic on external request

0x11

Now the DMA Controller waits for a request of the external device to start the first transfer.

Configure and start external device.

When the DMA Controller starts its first transfer, it sets the external acknowledge signal to 0.

After finishing the whole DMA transaction, the DMA Controller sets the external acknowledge

signal to 1.

TMPR3916 Datasheet(PDF) 116 Page - Toshiba Semiconductor

TMPR3916 Datasheet(HTML) 116 Page - Toshiba Semiconductor

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