AN2675

Theory of operation

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1

Theory of operation

1.1

IAP overview

In-Application Programming (IAP) is used to update the contents of the Flash memory in the

field without the use of any special hardware tool. To update firmware, the user must run the

IAP application that downloads the new firmware to the Flash memory.

The flowchart of the IAP driver is given below:

Figure 1.

Flowchart of the IAP driver

1.2

IAP using Ethernet on STR9

1.2.1

Ethernet interface

STR91xFA devices in 128-pin and 144-pin packages provide an IEEE-802.3-2002 compliant

Media Access Controller (MAC) for Ethernet LAN communications through an industry

standard Medium Independent Interface (MII). The STR91xFA requires an external Ethernet

physical interface device (PHY) to connect to the physical LAN bus (twisted-pair, fiber, etc.).

1.2.2

IAP using Ethernet

The principle of the IAP over Ethernet consists of loading the new firmware from a PC via

network.

The IAP application over Ethernet should be built on top of a TCP/IP suite protocol.

Start

Enter

IAP?

IAP initialization

Load Data

Jump to user application

No

Yes