10
MachXO Standard Evaluation Board
Lattice Semiconductor
Revisions 001 & 002 User’s Guide
LED Displays
On the south edge of the board is a set of eight green 0603 form factor LEDs. These LEDs are connected to I/O
pins dedicated to driving the LEDs. Table 7 shows which MachXO I/O controls each LED. The LEDs illuminate
when the corresponding I/O is driven to V
OL
.
Table 7. LED Pin Assignments
Switches
The evaluation board includes an eight-bit input toggle switch at the south edge of the board. The MachXO I/O
location for each bit in the switch is indicated on the PCB silkscreen. When in the up position, the switch is pulled to
3.3V via a 10K resistor. When in the down position, the switch is tied to ground.
Table 8. Switch Assignments
Oscillator and Clock Inputs
The MachXO Standard Evaluation Board provides the ability to supply selectable reference frequencies to the
MachXO device. The board provides a unique clock source distribution method. A Lattice ispClock5610 is included
on the board to provide a number of different clock frequencies to the MachXO device.
The ispClock5610 receives a reference clock from one of two sources on the board. The primary clock source for
the ispClock5610 is the on-board DIP oscillator. In the southwest corner of the board is XU1. This is a socket for
installing 300mil wide 3.3V DIP oscillators. Figure 7 shows how each type of oscillator can be placed in the DIP
socket.
LED
MachXO I/O
D0
R11
D1
R12
D2
P11
D3
P12
D4
T13
D5
T12
D6
R13
D7
R14
Switch
MachXO I/O
1
T3
2
R4
3
R5
4
P5
5
P6
6
T4
7
T5
8
R6
