Dma Modes - Analog Devices SHARC ADSP-214 Series Hardware Reference Manual

7. Configure the logical channel using the
mode, transfer direction, channel type, channel address and inter-
rupt generation.
For a transmit, a transmit service request, (
MLB_CSCRx
nel buffer can accept data. Within the ISR, check if this status bit is
set. If set, write the data into transmit data buffer (
For a receive, a receive service request, (
register) an interrupt is generated when the local channel buffer has
data to be read. Within the ISR, check if this status bit is set. If set,
read the data from the receive data buffer (
8. Clear all interrupts by writing 0x0000FFFF to the
register.

DMA Modes

MLB channels can be configured for circular buffer DMA mode by pro-
gramming the channel mode select bits (
01) for synchronous channels only. In contrast to DMA mode with
ping-pong buffering, circular buffering uses a single, circular memory buf-
fer to process channel data.
To configure a ping-pong or circular buffered DMA, use the following
procedure.
1. Reset the MLB device.
2. Program the appropriate bits in the
interrupt.
3. Unmask the appropriate bits in the
monitor the MLB network.
ADSP-214xx SHARC Processor Hardware Reference
www.BDTIC.com/ADI
register) an interrupt is generated when the local chan-
Media Local Bus
register for I/O
MLB_CECRx
bit 1 in the
STS
MLB_CNBCRx
bit 2 in the
STS
MLB_CCBCRx
MLB_CSCRx
register, bits 25–26 =
MLB_CECRx
register to generate MLB
PICRx
register inorder to
MLB_SSCR
).
MLB_CSCRx
).
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