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2x EtronTech EM636165-6G 1M x 16bit 166MHz SDRAMs (organized as 1M x 32bit) (datasheet)
12x TC74VHC245 Octal Bidirectional Transceiver (used for level translation to 5V) (datasheet)
PCB overview
FPGA connections
JTAG
JTAG is available on a 4-pin header next to the FPGA (U33). VCC/GND are available on a 2-pin header nearby.
Pin
Function
J27
TCK
J31
TMS
J32
TDI
J30
TDO
J33
3.3V
J34
GND
LED / Button
The board has a FPGA controlled LED and a button, those signals are also accessible on the J19 connector
Pin
Function
Note
U16
LED D2
Active low
R16
Button J28
Active low, pulled up with 10k
SPI Flash (U31)
Flash Pin
FPGA Pin
Function
Notes
1
R2
CS#
2
V2
SO
3
na
WP#
Wired to 3v3
4
na
GND
5
W2
SI
6
U3
SCK
7
na
Hold#
Wired to 3v3
8
na
VCC
Wired to 3v3
SDRAM (U29 & U32)
The two SDRAMs are configured as 1M x32 with the address and control signals shared and the data signals independently routed to the FPGA.
SDRAM Signal
FPGA Pin for U29
FPGA Pin for U32
Notes
DQ[0]
D15
D5
DQ[1]
E14
C5
DQ[2]
E13
D6
DQ[3]
D12
C6
DQ[4]
E12
E7
DQ[5]
D11
D7
DQ[6]
C10
E8
DQ[7]
B17
D8
DQ[8]
B8
E9
DQ[9]
A8
D9
DQ[10]
C7
E11
DQ[11]
A7
C11
DQ[12]
A6
C12
DQ[13]
B6
D13
DQ[14]
A5
D14
DQ[15]
B5
C15
A[0]
B13
B13
A[1]
C14
C14
A[2]
A16
A16
A[3]
A17
A17
A[4]
B16
B16
A[5]
B15
B15
A[6]
A14
A14
A[7]
A13
A13
A[8]
A12
A12
A[9]
A11
A11
A[10]
B12
B12
A[11]
B11
B11
LDQM
na
na
Wired to GND
UDQM
na
na
Wired to GND
WE#
A10
A10
CAS#
A9
A9
RAS#
B10
B10
CS#
na
na
Wired to GND
CKE
na
na
Wired to 3v3
CLK
B9
B9
Gigabit PHYs (U3 & U7)
PHY Signal
FPGA Pin for U3
FPGA Pin for U7
Notes
MDC
N5
N5
MDIO
P5
P5
Reset#
P4
P4
PHYA[0]
wired to GND
wired to 3v3
Fixes each PHY to different address
XTALO
P3
na
Provides a 25 MHz clock to the FPGA
GTXCLK
G1
U19
TXD[0]
G2
U20
TXD[1]
H1
T19
TXD[2]
J1
T20
TXD[3]
J3
R20
TX_EN
K1
P19
RXC
H2
L19
RXD[0]
K2
P20
RXD[1]
L1
N19
RXD[2]
N1
N20
RXD[3]
P1
M19
RX_DV
P2
M20
HUB75 headers
J1
HUB75 Pin
HUB75 Signal
FPGA Pin
Buffer chip / bit
Function
HI SPEED
1
R0
B3
U28.7
PL5D
n
2
G0
A2
U28.6
PL14A
y
3
B0
B2
U28.5
PL14C
n
5
R1
B1
U28.4
PL14B
y
6
G1
C2
U28.2
PL14D
n
7
B1
C1
U28.3
PL17A
y
9
A
F1
U10.2
PL26B
y
10
B
E2
U10.4
PL23D
n
11
C
E1
U10.6
PL17D
n
12
D
F2
U10.0
PL23C
n
8
E
J17
U17.2
PR11C
n
13
Clock
C18
U17.4
PL26B
y
14
Latch
J18
U17.0
PL41A
y
15
Blank
H16
U17.6
PR8D
n
J2
HUB75 Pin
HUB75 Signal
FPGA Pin
Buffer chip / bit
Function
HI SPEED
1
R0
D2
U28.1
PL17C
n
2
G0
H3
U28.0
PL20D
n
3
B0
H4
U24.7
PL20A
y
5
R1
J4
U24.6
PL29A
y
6
G1
B4
U24.5
PL5B
y
7
B1
A3
U24.4
PL5C
n
9
A
F1
U10.2
PL26B
y
10
B
E2
U10.4
PL23D
n
11
C
E1
U10.6
PL17D
n
12
D
F2
U10.0
PL23C
n
8
E
J17
U17.2
PR11C
n
13
Clock
C18
U16.4
PL26B
y
14
Latch
J18
U16.0
PL41A
y
15
Blank
H16
U16.6
PR8D
n
J3
HUB75 Pin
HUB75 Signal
FPGA Pin
Buffer chip / bit
Function
HI SPEED
1
R0
D1
U24.3
PL17B
y
2
G0
J5
U24.2
PL29B
y
3
B0
K4
U24.1
PL35A
y
5
R1
K5
U24.0
PL35B
y
6
G1
K3
U23.7
PL29D
n
7
B1
E5
U23.6
PL11C
n
9
A
F1
U10.3
PL26B
y
10
B
E2
U10.5
PL23D
n
11
C
E1
U10.7
PL17D
n
12
D
F2
U10.1
PL23C
n
8
E
J17
U17.3
PR11C
n
13
Clock
C18
U16.5
PL26B
y
14
Latch
J18
U16.1
PL41A
y
15
Blank
H16
U16.7
PR8D
n
J4
HUB75 Pin
HUB75 Signal
FPGA Pin
Buffer chip / bit
Function
HI SPEED
1
R0
N3
U23.5
PL41A
y
2
G0
N4
U23.4
PL38C
n
3
B0
R3
U23.3
PB15B
n
5
R1
T3
U23.2
PB18A
n
6
G1
R1
U23.1
PB4A
n
7
B1
T1
U23.0
PB4B
n
9
A
F1
U10.3
PL26B
y
10
B
E2
U10.5
PL23D
n
11
C
E1
U10.7
PL17D
n
12
D
F2
U10.1
PL23C
n
8
E
J17
U17.3
PR11C
n
13
Clock
C18
U17.5
PL26B
y
14
Latch
J18
U17.1
PL41A
y
15
Blank
H16
U17.7
PR8D
n
J5
HUB75 Pin
HUB75 Signal
FPGA Pin
Buffer chip / bit
Function
HI SPEED
1
R0
U17
U9.6
PR47B
y
2
G0
U18
U9.7
PR47A
y
3
B0
T17
U9.5
PR47D
n
5
R1
T18
U9.3
PR44D
n
6
G1
K20
U9.4
PR23D
n
7
B1
L20
U9.2
PR26A
y
9
A
F1
U22.0
PL26B
y
10
B
E2
U22.6
PL23D
n
11
C
E1
U22.4
PL17D
n
12
D
F2
U22.2
PL23C
n
8
E
J17
U20.2
PR11C
n
13
Clock
C18
U20.0
PL26B
y
14
Latch
J18
U20.4
PL41A
y
15
Blank
H16
U20.6
PR8D
n
J6
HUB75 Pin
HUB75 Signal
FPGA Pin
Buffer chip / bit
Function
HI SPEED
1
R0
J20
U9.0
PR23C
n
2
G0
K19
U9.1
PR23B
y
3
B0
J19
U12.7
PR23A
y
5
R1
G20
U12.5
PR17D
n
6
G1
H20
U12.6
PR20B
y
7
B1
G19
U12.4
PR20A
y
9
A
F1
U22.0
PL26B
y
10
B
E2
U22.6
PL23D
n
11
C
E1
U22.4
PL17D
n
12
D
F2
U22.2
PL23C
n
8
E
J17
U20.2
PR11C
n
13
Clock
C18
U21.0
PL26B
y
14
Latch
J18
U21.4
PL41A
y
15
Blank
H16
U21.6
PR8D
n
J7
HUB75 Pin
HUB75 Signal
FPGA Pin
Buffer chip / bit
Function
HI SPEED
1
R0
F19
U12.2
PR17B
y
2
G0
F20
U12.3
PR17C
n
3
B0
E20
U12.1
PR17A
y
5
R1
D20
U15.7
PR14C
n
6
G1
E19
U12.0
PR14D
n
7
B1
D19
U15.6
PR14B
y
9
A
F1
U22.1
PL26B
y
10
B
E2
U22.7
PL23D
n
11
C
E1
U22.5
PL17D
n
12
D
F2
U22.3
PL23C
n
8
E
J17
U20.3
PR11C
n
13
Clock
C18
U21.1
PL26B
y
14
Latch
J18
U21.5
PL41A
y
15
Blank
H16
U21.7
PR8D
n
J8
HUB75 Pin
HUB75 Signal
FPGA Pin
Buffer chip / bit
Function
HI SPEED
1
R0
B20
U15.4
PT67B
n
2
G0
C20
U15.5
PR14A
y
3
B0
B19
U15.3
PT65B
n
5
R1
B18
U15.1
PT62B
n
6
G1
A19
U15.2
PT67A
n
7
B1
A18
U15.0
PT65A
n
9
A
F1
U22.1
PL26B
y
10
B
E2
U22.7
PL23D
n
11
C
E1
U22.5
PL17D
n
12
D
F2
U22.3
PL23C
n
8
E
J17
U20.3
PR11C
n
13
Clock
C18
U20.1
PL26B
y
14
Latch
J18
U20.5
PL41A
y
15
Blank
H16
U20.7
PR8D
n
Buffering architecture
The buffers are powered directly from the raw input voltage (nominal 5V) and translate between the FPGA 3v3 to the voltage required for the panels.
Address lines
Line all control signals, the address lines A, B, C, D all share a single FPGA pin. That signal is then buffered several times in parallel with each buffer output going through a 33R and then to two adjacent HUB75 connectors.
The address line E is a bit special and there are additional 22R resistors in series with the connection to each pin. this is most likely to deal with the fact that the E line is a re-used GND pin and so some panels might short it to GND.
Misc control lines
The control lines CLK, LATCH, BLANK also share a single FPGA pin but each connector has its own buffer and inline 33R resistor.
Data lines
Those are the simplest, all independent, one buffer per data bit with a 33R in series.
"Usable" LVDS Pairs
The LVDS in ECP5 are in always in pairs of A/B and C/D. But only the Left and Right banks has true hardware lvds support. The Top and Bottom have emulated LVDS and need external impedance match. The True LVDS support is denoted in the table.
Notice that you will need to remove the corresponding level shifter from the board along with the resistors to correct use the LVDS ports.