PRELIMINARY
CYW54907
5.10 UART
A high-speed 4-wire CTS/RTS UART interface can be enabled by software and has dedicated pins. Provided primarily for debugging
during development, this UART enables the CYW54907 to operate as RS-232 data termination equipment (DTE) for exchanging and
managing data with other serial devices. It is compatible with the industry standard 16550 UART and provides a FIFO size of 64 × 8
in each direction.
There are two low-speed UART interfaces on the CYW54907. Each functions as a standard 2-wire UART. They are also enabled as
alternate functions on GPIOs and can be enabled independently of the 4-wire fast UART.
Note: The high-speed, 4-wire UART interface is identified as UART0 in this document and in reference schematics. The two low-
speed, 2-wire UART interfaces are identified as UART1 and UART2 in this document and in the reference schematics.
5.11 USB 2.0
5.11.1 Overview
The USB 2.0 host controller (HC) and device controller (DC) interface to a backplane via Advanced extensible Interface (AXI) and
Advanced Peripheral Bus (APB). They interface externally through a USB 2.0 and HSIC interfaces.
Figure 8 shows the topology of the USB 2.0 core.
Figure 8. Topology of the USB 2.0 Core
AXI/APB
USB Device
Controller
USB Host
Controller
APB
UTMI/ULPI
UTMI/ULPI
Host/
Device
Select
Multiplexer
UTMI/ULPI
USB 2.0 PHY
Chip
Boundary
USB I/F
The CYW54907 contains both a USB 2.0 HC and DC. Therefore, it can operate in the host-only, device-only, and dual-role device
(DRD) modes. In DRD mode, the CYW54907 can be configured as either the host or a device on the fly but must remain in the same
mode until the next boot cycle. The restriction that the host or device mode remains fixed during a boot cycle is what differentiates
DRD from On-the-Go (OTG).
The state of the USB2_DSEL pin sets the mode as either host or device for USB Type A and Type B connectors. For a USB Micro-
AB connector, the USB2_DSEL pin sets the mode as either host or device while the overall mode is DRD.
Document Number: 002-19312 Rev. *C
Page 21 of 95
CYPRESS [ CYPRESS ]
