Input/Output

I/O banks and special functions

Virtex 5 devices have up to three I/O columns:

• the left I/O column, containing only IO tiles; if the device has no transceivers on the left side, it is the leftmost column of the device; otherwise, it is somewhat to the right of the left GT column; it is always present
• the center column, part of which contains IO tiles; the IO tiles in this column come in up to four segments:
  • the lower segment (variable size, not present on all devices), between the bottom edge of the device and the lower CMTs
  • the lower middle segment (always 20 tiles high), between lower CMTs and the configuration center
  • the upper middle segment (always 20 tiles high), between the configuration center and the upper CMTs
  • the upper segment (variable size, not present on all devices), between the device and the upper CMTs and the top edge of the device
• the right I/O column, containing only IO tiles; it is present on all devices except for xc5vlx20t; if present, it is somewhat to the left of the device’s right edge

Virtex 5 has the following banks:

• bank 0 is the configuration bank; it contains only dedicated configuration I/O pins, as follows:

  • CCLK
  • CS_B
  • DONE
  • D_OUT_BUSY
  • D_IN
  • HSWAPEN
  • INIT
  • M0
  • M1
  • M2
  • PROGRAM_B
  • RDWR_B
  • TCK
  • TDI
  • TDO
  • TMS

  bank 0 is not associated with any IO tiles

• banks 1-4: middle segments of the center column; each of them consists of 10 IO tiles; they contain global clock inputs and shared configuration pins

  • bank 1: immediately above configuration center
  • bank 2: immediately below configuration center
  • bank 3: above bank 1, below upper CMTs (not present on xc5vlx20t)
  • bank 4: below bank 2, above lower CMTs

• banks 5-10: lower and upper segments of the center column; each of them consists of 20 IO tiles

  • banks 5, 7, 9 are the upper segment, with bank 5 being immediately above upper CMTs; bank number increases upwards
  • banks 6, 8, 10 are the lower segment, with bank 6 being immediately below lower CMTs; bank number increases downwards

• banks 11 and up: left and right column; each of them consists of 20 IO tiles

  • banks 11, 15, 19, 23, …: left column, above the configuration center; bank number increases upwards, starting from bank 11 immediately above the configuration center row
  • banks 12, 16, 20, 24, …: right column, above the configuration center; bank number increases upwards, starting from bank 12 immediately above the configuration center row
  • banks 13, 17, 21, 25, …: left column, below the configuration center; bank number increases downwards, starting from bank 13 immediately below the configuration center row
  • banks 14, 18, 22, 26, …: right column, below the configuration center; bank number increases downwards, starting from bank 14 immediately below the configuration center row

All IOBs in the device are grouped into differential pairs, one pair per IO tile. IOB1 is the “true” pin of the pair, while IOB0 is the “complemented” pin. Differential input and true differential output is supported on all pins of the device.

IOB1 pads in the 4 rows surronding the HCLK row (that is, in rows 8-11 of every clock region) are considered “clock-capable”. They can drive BUFIO and BUFR buffers via dedicated connections. While Xilinx documentation also considers IOB0 pads clock-capable, this only means that they can be used together with IOB1 as a differential pair.

The IOB1 pads in banks 3 and 4 are considered “global clock-capable”. They can drive BUFGCTRL buffers and CMT primitives via dedicated connections. Likewise, Xilinx considers IOB0 pads to be clock-capable, but they can only drive clocks as part of differential pair with IOB1.

The IOB0 in rows 5 and 15 of every region is capable of being used as a VREF pad.

Each bank except for banks 1 and 2 has two IOBs that can be used for reference resistors in DCI operation. They are both located in the same I/O tile, with VRP located on IOB0 and VRN located on IOB1. The relevant tile is located as follows:

• bank 1 and 2: VRP/VRN are not present in this bank (DCI can still be used by cascade from banks 3 and 4)
• bank 3: row 7 of the bank (or row 7 of the region)
• bank 4: row 2 of the bank (or row 12 of the region)
• banks 5 and up: row 7 of the bank (or row 7 of the region)

In parallel configuration modes, some I/O pads in banks 1-4 are borrowed for configuration use, as the parallel data pins:

• bank 4 row 6 IOB0: D[8]
• bank 4 row 6 IOB1: D[9]
• bank 4 row 7 IOB0: D[10]
• bank 4 row 7 IOB1: D[11]
• bank 4 row 8 IOB0: D[12]
• bank 4 row 8 IOB1: D[13]
• bank 4 row 9 IOB0: D[14]
• bank 4 row 9 IOB1: D[15]
• bank 2 row 0 IOB0: D[0]/FS[0]
• bank 2 row 0 IOB1: D[1]/FS[1]
• bank 2 row 1 IOB0: D[2]/FS[2]
• bank 2 row 1 IOB1: D[3]
• bank 2 row 2 IOB0: D[4]
• bank 2 row 2 IOB1: D[5]
• bank 2 row 3 IOB0: D[6]
• bank 2 row 3 IOB1: D[7]
• bank 2 row 4 IOB0: CSO_B
• bank 2 row 4 IOB1: FWE_B
• bank 2 row 5 IOB0: FOE_B/MOSI
• bank 2 row 5 IOB1: FCS_B
• bank 2 row 6 IOB0: A[20]
• bank 2 row 6 IOB1: A[21]
• bank 2 row 7 IOB0: A[22]
• bank 2 row 7 IOB1: A[23]
• bank 2 row 8 IOB0: A[24]
• bank 2 row 8 IOB1: A[25]
• bank 2 row 9 IOB0: RS[0]
• bank 2 row 9 IOB1: RS[1]
• bank 1 row 0 IOB0: D[16]/A[0]
• bank 1 row 0 IOB1: D[17]/A[1]
• bank 1 row 1 IOB0: D[18]/A[2]
• bank 1 row 1 IOB1: D[19]/A[3]
• bank 1 row 2 IOB0: D[20]/A[4]
• bank 1 row 2 IOB1: D[21]/A[5]
• bank 1 row 3 IOB0: D[22]/A[6]
• bank 1 row 3 IOB1: D[23]/A[7]
• bank 1 row 4 IOB0: D[24]/A[8]
• bank 1 row 4 IOB1: D[25]/A[9]
• bank 1 row 5 IOB0: D[26]/A[10]
• bank 1 row 5 IOB1: D[27]/A[11]
• bank 1 row 6 IOB0: D[28]/A[12]
• bank 1 row 6 IOB1: D[29]/A[13]
• bank 1 row 7 IOB0: D[30]/A[14]
• bank 1 row 7 IOB1: D[31]/A[15]
• bank 1 row 8 IOB0: A[16]
• bank 1 row 8 IOB1: A[17]
• bank 1 row 9 IOB0: A[18]
• bank 1 row 9 IOB1: A[19]

The SYSMON present on the device can use up to 16 IOB pairs from the left I/O column as auxiliary analog differential inputs. The VPx input corresponds to IOB1 and VNx corresponds to IOB0 within the same tile. The IOBs are in the following tiles, where r is the configuration center row:

• VP0/VN0: left I/O column, row r - 10
• VP1/VN1: left I/O column, row r - 9
• VP2/VN2: left I/O column, row r - 8
• VP3/VN3: left I/O column, row r - 7
• VP4/VN4: left I/O column, row r - 6
• VP5/VN5: left I/O column, row r - 4
• VP6/VN6: left I/O column, row r - 3
• VP7/VN7: left I/O column, row r - 2
• VP8/VN8: left I/O column, row r - 1
• VP9/VN9: left I/O column, row r
• VP10/VN10: left I/O column, row r + 1
• VP11/VN11: left I/O column, row r + 2
• VP12/VN12: left I/O column, row r + 3
• VP13/VN13: left I/O column, row r + 4
• VP14/VN14: left I/O column, row r + 8
• VP15/VN15: left I/O column, row r + 9

Tile IO

Cells: 1

Bel ILOGIC0

Bel ILOGIC1

Bel OLOGIC0

Bel OLOGIC1

Bel IODELAY0

Bel IODELAY1

Bel IOB0

Bel IOB1

Bel IOI

Bel wires

Bitstream

Tables