Designing Hardware for QuickUSB
FX2128
Pin
QUSB2
Pin
Name
Dir
Desc
Function
101 74
WAKEUP_
B
Input
USB Wakeup USB Wakeup. Asserting pin brings
FX2 out of suspend mode. Active
Low. Not used, connected to VCC
through a 10k resistor on QuickUSB
Module.
19 N/A
DMINUS
I/O
USB
D-
Signal
Connect to the USB D- Signal
18 N/A DPLUS I/O
USB
D+
Signal
Connect to the USB D+ Signal
94 N/A A0 Output
95 N/A A1 Output
96 N/A A2 Output
97 N/A A3 Output
117 N/A A4 Output
118 N/A A5 Output
119 N/A A6 Output
120 N/A A7 Output
126 N/A A8 Output
127 N/A A9 Output
128 N/A A10 Output
21 N/A A11 Output
22 N/A A12 Output
23 N/A A13 Output
24 N/A A14 Output
25 N/A A15 Output
8051 Address
Bus
8051 Address Bus. Driven at all
times. Reflects internal address when
8051 is addressing RAM. Not
connected on QuickUSB Module.
59 N/A D0 I/O
60 N/A D1 I/O
61 N/A D2 I/O
62 N/A D3 I/O
63 N/A D4 I/O
86 N/A D5 I/O
87 N/A D6 I/O
88 N/A D7 I/O
8051 Data
Bus
8051 Data Bus. Bi-directional bus
used for external 8051 program and
data memory. High Impedance when
inactive. Active only for external bus
accesses. Driven low in suspend. Not
connected on QuickUSB Module.
39 N/A PSEN#
Output
Program
Store Enable
Indicates an 8051 code fetch from
external memory. Active low.
34 N/A BKPT
Output
Breakpoint
Used as SW_EN on the QuickUSB
module to control the onboard VBUS
switch.
35 N/A EA Input
External
Access
Determines where the 8051 fetches
code from RAM. If EA=0, 8051
fetches from internal Ram. If EA=1,
8051 fetches from external RAM. Tied
to GND through 10k Resistor on
QuickUSB Module.
12
N/A
XTALIN
Input
Crystal Input Connect to 24MHz parallel resonant,
fundamental mode crystal and
connect the parallel load capacitor to
GND.
11 N/A
XTALOUT
Output
Crystal
Output
Connect to 24MHz parallel resonant,
fundamental mode crystal and
connect the parallel load capacitor to
GND.
42 N/A CS# Output
External
Memory Chip
Select
External Memory Chip Select. Active
Low. Not connected on QuickUSB
Module
36
QuickUSB Pin Definitions