Programmers Model
ARM DUI 0447J
Copyright © 2009-2014, ARM. All rights reserved.
4-39
ID052914
Non-Confidential
Enabling UARTs
You must set the variables MBLOG and DBLOG in the
config.txt
file to FALSE to enable you
to use the UARTs.
Example 4-2
shows the lines in the
config.txt
file that you must edit to enable the UARTs.
Example 4-2 Example code in
config.txt
file to enable UARTs
MBLOG: FALSE
;LOG MB MICRO TO UART1 in run mode
DBLOG: FALSE
;LOG DB MICRO TO UART2/3 in run mode
See the
ARM
®
Versatile
™
Express Configuration Technical Reference Manual
for information
on how to edit the
config.txt
file.
4.5.11
USB interface
The USB interface is provided by a Philips ISP1761 controller that provides a standard USB
host controller and an
On-The-Go
(OTG) dual role device controller. The USB host has two
downstream ports. The OTG can function as either a host or slave device.
The internal registers of the USB interface are memory-mapped onto a static memory bus chip
select. The chip select that they map onto depends on the memory map your daughterboard is
using as follows:
•
ARM legacy memory map:
—
The registers map onto the CS3 chip select.
•
Cortex-A Series
memory map:
—
The registers map onto the CS2 chip select.
Note
See the Technical Reference Manual for your daughterboard.
Table 4-36
provides information about the USB interface.
Table 4-36 USB implementation
Property
Value
Location
Motherboard IO FPGA
Memory base address
•
ARM Legacy memory map:
—
SMB CS3 base a
0x03000000
•
ARM Cortex-A Series
memory map:
—
SMB CS2 base a
0x03000000
Interrupt
16
DMA
None
Release version
Custom interface to external controller
Reference documentation
ISP1761 Hi-Speed Universal Serial Bus On-The-Go controller Product data sheet