3

ATSAM9708

1772D–DRMSD–01/04

Pin Description by Function

Notes:

1. ISA bus group pins are powered by V

2. PC_D pads have 4 mA drive capabilities; other output pads have 16 mA drive capabilities.

3. To interface with PC ISA bus, V

PC_RD signal.

4. Pin Names in this document exhibiting an overbar (PC_CS for example) indicates that the signal is active low.

Table 1. Power Group

Name

Pin Count

Type

Function

GND

19

PWR

Power Ground. All GND pins should be returned to digital ground.

VC3

8

PWR

Core Power, +3.3V nominal (3V to 4.5V). All V

+3.3V.

VCC1

5

PWR

Pad (except Memory Pad) Power, +3.0V to +5.5V. All V

returned to +5V (or 3.3V in case of single 3.3V supply).

VCC2

5

PWR

Memory Pad Power, +3.0V to +5.5V. All V

RAM or DRAM) or 3.3V (for SDRAM or 3.3V ROM).

Table 2. ISA Bus Group

(1)

Name

Pin Count

Type

Function

16

I/O

16-bit data bus to host processor.

Information on these pins is:

- 2 x parallel MIDI (MPU-401 type applications)

- 2 x high-speed burst data transfers to/from external memory

PC_A[2:0]

3

IN

Selects one of 8 internal registers:

0, 1: MPU-401 register processor #1

2, 3: Burst data (16-bit) processor #1

4 - 5: MPU-401 register processor #2

6 - 7: Burst data (16-bit) processor #2

1

IN

Chip select from host, active low.

PC_WR

1

IN

Write from host, active low.

PC_RD

1

IN

Read from host, active low.

PC_READY

1

TSout

Open drain output buffer. Driven low during 16-bit burst mode transfers to

synchronize host to the ATSAM9708 memory.

PC_IO16

1

TSout

Open drain output buffer; driven low during 16-bit burst mode transfers.

Indicates to host that a 16-bit I/O is in progress.

PC_IRQ

1

TSout

Tri-state output pin, active high. Can be connected directly to host PC_IRQ line.