The ISP1161 is a single-chip Universal Serial Bus (USB) Host Controller (HC) and
Device Controller (DC) which complies with Universal Serial Bus Specification
Rev 1.1. These two USB controllers, the HC and the DC, share the same
microprocessor bus interface. They have the same data bus, but different I/O
locations. They also have separate interrupt request output pins, separate DMA
channels that include separate DMA request output pins and DMA acknowledge
input pins. This makes it possible for a microprocessor to control both the USB HC
and the USB DC at the same time.
ISP1161 provides two downstream ports for the USB HC and one upstream port for
the USB DC. Each downstream port has its own overcurrent (OC) detection input pin
and power supply switching control output pin. The upstream port has its own VBUS
detection input pin. ISP1161 also provides separate wakeup input pins and
suspended status output pins for the USB HC and the USB DC, respectively. This
makes power management flexible. The downstream ports for the HC can be
connected with any USB compliant USB devices and USB hubs that have USB
upstream ports. The upstream port for the DC can be connected to any USB
compliant USB host and USB hubs that have USB downstream ports.
The DC is compliant with most device class specifications such as Imaging Class,
Mass Storage Devices, Communication Devices, Printing Devices and Human
Interface Devices.
ISP1161 is well suited for embedded systems and portable devices that require a
USB host only, a USB device only, or a combined and configurable USB host and
USB device capabilities. ISP1161 brings high flexibility to the systems that have it
built-in. For example, a system that has ISP1161 built-in allows it not only to be
connected to a PC or USB hub that has a USB downstream port, but also to be
connected to a device that has a USB upstream port such as a USB printer, USB
camera, USB keyboard, USB mouse, among others. ISP1161 enables peer-to-peer
connectivity between embedded systems. An interesting application example is to
connect a ISP1161 HC with a ISP1161 DC.
Let us see an example of ISP1161 being used in a Digital Still Camera (DSC) design.
Figure 1 shows ISP1161 being used as a USB DC. Figure 2 shows ISP1161 being
used as a USB HC. Figure 3 shows ISP1161 being used as a USB HC and a USB
DC at the same time.