Artesyn COMX-P2020 Installation and Use (July 2014) - Manual (Page 84)

Functional Description
COMX-P2020 COM Express Module Installation and Use (6806800K97D) 84
4.11 UART
The COMX-P2020 COM Express Module consists of two universal asynchronous
receiver/transmitters (UARTs). The UARTs act independently. Each UART is clocked by the
platform clock (600MHz). The DUART programming model is compatible with the PC16552D.
U-boot will use the following parameters to initialize the UARTs:
4.12 USB
P2020 implements a dual-role (DR) USB module. This module is connected to USB2514i which
can provide 4 downstream ports. The DR module can act as a device or host controller, while
in this case, it is configured as a host controller, and it can support at most six bidirectional USB
endpoints.
4.13 PCI Express
There are three PCI Express on COMX-P2020 . The PCI Express are configured as:
PCI Express 1 x1 (2.5 Gbps) SerDes lane 0
Table 4-2 Initialization Parameters
Parameter Value
Baud rate 115200
Data bit 8
Parity None
Stop bit 1
CCB Clock 400 MHz
Divisor most and least significant byte registers CCB Clock / Baud rate / 16 = 326
Internal interrupt number 26