11
LatticeMico32/DSP Development Board
Lattice Semiconductor
User’s Guide
Table 12. Serial Interface X1C Pin Definitions
Sigma Delta D/A Converter
The board includes a low-pass filter connected to a dedicated pin of the FPGA. With this, a sigma delta converter
can be realized. Great results can be achieved by using a resolution of 8 to 10 bits. Example VHDL code is pro-
vided.
Power Supply
Four different voltages are needed: 3.3V I/O voltage, 2.5V DDR and LVDS voltages as well as 1.2V core voltage.
The 3.3V supply draws up to 1A, the 2.5V and 1.2V supplies up to 2A of current.
For more information, see the power supply information in the Components section of this document.
Test Points
In order to check the various voltage levels used, several test points are provided. There is one test point for 1.2V,
2.5V, 3.3V, one for ground, and one for accessing the 25MHz oscillator. The 25MHz clock signal can be checked
with another test point.
USB Host/Peripheral Interface
There are one USB peripheral and two USB host connectors on board. These are connected to the Cypress
CY7C67300 USB Host/Peripheral Controller U0702. This controller is compliant with the Universal Serial Bus
Specification 2.0. You can transmit and receive serial data at both full-speed (12 Mbps) and low-speed (1.5 Mbps)
data rates. For more information, please refer to the data sheet of the USB controller. U0703 and U0704 are USB
power control switches, which must be enabled by the user via the USB PWEN signals. The USB OC signal pulls
low to indicate voltage, current and thermal issues.
Table 13. USB GPIO Connections (U0702)
Signal
Direction
Sub-D Pin
RS232 Function
FPGA Pin
RS TXD LVTTL
Out
3
Transmit Data
L1
RS RTS LVTTL
Out
7
Request to Send
L2
RS RXD LVTTL
In
2
Receive Data
M2
RS CTS LVTTL
In
8
Clear to Send
M1
Pin
Signal Name
FPGA Pin
Pin
Signal Name
FPGA Pin
94
USB GPIO0
B7
93
USB GPIO1
C7
92
USB GPIO2
D7
91
USB GPIO3
E7
90
USB GPIO4
F7
89
USB GPIO5
A8
87
USB GPIO6
B8
86
USB GPIO7
C8
66
USB GPIO8
D8
65
USB GPIO9
E8
61
USB GPIO10
F8
60
USB GPIO11
A9
59
USB GPIO12
B9
58
USB GPIO13
C9
57
USB GPIO14
D9
56
USB GPIO15
E9
55
USB GPIO16
F9
54
USB GPIO17
G9
53
USB GPIO18
B10
52
USB GPIO19
C10
50
USB GPIO20
D10
49
USB GPIO21
E10
48
USB GPIO22
F10
47
USB GPIO23
G10
46
USB GPIO24
B11
45
USB GPIO25
C11
44
USB GPIO26
D11
43
USB GPIO27
E11
42
USB GPIO28
E12
41
USB GPIO29
pulled up