NS7520B-1-I46 Digi International, NS7520B-1-I46 Datasheet - Page 140

• Manufacturer Part Number: NS7520B-1-I46
• Description: IC ARM MICROPROCESSOR 177BGA
• Manufacturer: Digi International
• Series: NET+ARM®r

Specifications of NS7520B-1-I46

• Applications: Network Processor
• Core Processor: ARM7
• Program Memory Type: External Program Memory
• Controller Series: -
• Ram Size: External
• Interface: EBI/EMI, Ethernet, DMA, SPI, UART
• Number Of I /o: 16
• Voltage - Supply: 1.4 V ~ 3.6 V
• Operating Temperature: -40°C ~ 85°C
• Mounting Type: Surface Mount
• Package / Case: 177-LFBGA
• Lead Free Status / Rohs Status: Lead free / RoHS Compliant

Fly-by operation transfers
1 2 8
D M A m o d u l e
DMA module
Each DMA controller has a state machine and a block of static RAM referred to as
context RAM.
Figure 15: DMA controller block diagram
The DMA controller arbiter determines which channel the state machine currently is
operating.
There are two modes of fly-by operation:
When configured for fly-by operation, the DMA controller transfers data between one
of the NS7520 internal peripherals and a memory location. The DMA controller does
Channel
transfer
attributes
The context RAM contains the current state of each DMA channel.
The single state machine supports all DMA channels in parallel, by context
switching from channel to channel.
Read mode. Transfers data from memory to a peripheral device.
Write mode. Transfers data from a peripheral device to memory.
BBus
N S 7 5 2 0 H a r d w a r e R e f e r e n c e , R e v G 9 / 2 0 0 7
Bus interface
DMA channel
arbiter
DMA control
state machine
DMA
context RAM
128 x 32
Data
in
Data
out