NS7520B-1-I46 Digi International, NS7520B-1-I46 Datasheet - Page 120

• 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

Table 41: Internal DRAM multiplexing — Mode 1
Using the external multiplexer
1 0 8
N S 7 5 2 0 D R A M a d d r e s s m u l t i p l e x i n g
NS7520
pin
DRAM
pin
RAS
CAS
NS7520
pin
DRAM
pin
RAS
CAS
A23
16-bit DRAM peripheral (22 address bits: 14 RAS and 8 CAS)
A23
A13
23
23
32-bit DRAM peripheral (22 address bits: 14 RAS and 8 CAS)
NS7520 multiplexed address outputs
An external address multiplexer is required when the selected SDRAM component
cannot interface with the NS7520 internal multiplexer. Although an external address
multiplexer is used, the NS7520 memory controller can control the basic DRAM signal
protocol. The NS7520 can be configured to output the DRAM address multiplexer
signal out the PORTA2 pin, by setting the AMUX or AMUX2 bit in the MMCR or by
setting the DMUXS bit in the Chip Select Base Address register.
Setting the AMUX bit indicates that the internal address multiplexer must be
disabled. When AMUX is set, the NS7520 drives the address bus using standard
addressing without any multiplexing, the internal multiplexer is disabled, and the
multiplexer indicator is driven out the PORTA2 pin.
The AMUX2 bit allows the internal bus masters to use the internal address
multiplexer, and forces the PORTA2 signal to be driven.
A22
A13
22
22
A22
A12
22
22
A13
A13
A11
A12
21
0
21
0
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
A12
A12
A10
A11
20
0
20
0
A11
A11
A9
A10
19
0
19
0
A10
A9
18
10
A10
A8
18
10
A9
A8
17
9
A9
A7
17
9
A8
A7
A8
A6
16
8
16
8
A7
A6
15
7
A7
A5
15
7
A6
A5
14
6
A6
A4
14
6
A5
A4
13
5
A5
A3
13
5
A4
A3
12
4
A4
A2
12
4
A3
A2
11
3
A3
A1
11
3
A2
A1
10
2
A2
A0
10
2
A1
A0
9
1
A1
A0
A0