Designing Hardware for QuickUSB
FPGA Configuration
The QuickUSB Plug-In module can configure SRAM-based FPGA devices over the
USB. The configuration method that QuickUSB uses is based on the
setting of the ‘Settings’ section of this document.
Currently, two configuration schemes are supported: Altera Passive Serial and
Xilinx Slave Serial.
The QuickUSB module uses 3.3V I/O, so make sure your device can handle 3.3V
on the configuration pins. Then, connect the FPGA as shown in Table 6. You
must be sure to add pull-up resistors required by the FPGA manufacturer. Refer
to the FPGA manufacturer’s documentation for the proper configuration
connection pin out, signal level and device configuration mode. QuickUSB can
transfer an unlimited number of configuration data blocks, so multiple daisy
chained devices can be configured using QuickUSB.
QuickUSB Signal
Altera PS
Xilinx Slave Serial
DATA0 DATA0
DIN
DCLK DCLK
CCLK
nCONFIG nCONFIG
PROGRAM
nSTATUS nSTATUS
INIT
CONF_DONE CONF_DONE
DONE
Table 6 - FPGA Configuration Signals
General-Purpose I/O Pins
The QuickUSB Module implements General Purpose I/O Pins on Ports A, B, C, D,
and E when not using the alternate functions for those ports. Please see the
‘
’ section of this user guide for information on the ports
and which are being used for alternate functions.
RS-232
The QuickUSB Module’s RS-232 Ports provide standard asynchronous, full-
duplex communications. The RS-232 ports operate with no parity, eight data
bits, and one stop bit (N81). RS-232 data is received using interrupt-driven
receive routines in the module. Both ports operate at the same baud rate.
I2C
The QuickUSB I
2
C-compatible port is a master-only bus controller that can
operate in Standard Mode (100kHz) or Fast Mode (400kHz) with 7-bit
addressing. The bus speed is selectable using Bit 0 of SETTING_I2CTL. Address
81 (decimal) is reserved. The R/W bit is automatically inserted, so it does not
need to be included in the address. The address is automatically shifted to
accommodate the R/W bit.
FPGA
Configuration
21