Installation Instructions

Hardware Installation
RVP8 User’s Manual
September 2005
2–31
assure a valid TTL low level of 0.6V max. requires that the STALO inputs be pulled up to +5
with nothing less than (approx.) 1.2KW. Put another way, the low level input current of the
receiving device should not exceed 4.5mA. Most STALOs that we have seen use 5-20KW
pull-up resistors, so this should not be a problem.
All twenty five pins of the “D” connector are wired identically on the DAFC board, i.e., each pin
connects to one end of a 2-pin jumper (2x25 header H1), the other end of which connects to a
Programmable Logic Device (PLD) chip. The PLD lines can be configured either as inputs or
outputs, and this single chip handles all of the decoding and driving needs for the entire board.
For each “D” connector pin that is to be used as an AFC output or Fault Status input, you should
install the corresponding jumper to connect that pin through to the PLD, or use a wirewrap wire
if the pin must go to a different PLD line. The “D” connector pin numbers are printed next to
each of the jumper locations. Because of the ordering of the pins in the connector housing,
jumpers 1 through 13 are interleaved with jumpers 14 through 25.
The uplink protocol that the board should be expecting is selected by jumpers H3 and H4, as
summarized in Table 2–10. The first three table entries describe three fixed mappings of the
traditional AFC-16 uplink format onto various pins of the 25-pin “D” connector. One of these
choices must be used whenever the DAFC is interfaced to an RVP8 system whose uplink uses
the older style 16-bit AFC uplink format. In this case you will have to make most or all of the
pin assignments using wirewrap wire to connect each bit to its corresponding pin. This will be
somewhat tedious, but hopefully one of the three formats will be a reasonable starting point for
doing the wiring. By far the most preferable solution, however, is to use the Pinmap uplink
protocol (available since Rev.19) which allows for complete software mapping of all 25 external
pins.
Table 2–10: DAFC Protocol Jumper Selections
H4 H3 Function
On On AFC-16 format, Bits<0:15> on Pins<1:16>, Fault input on Pin 25
On Off AFC-16 format, Bits<0:15> on Pins<25:10>, Fault input on Pin 3
Off On AFC-16 format, Bits<0:15> on Pins<18, 19, 6, 7, 21, 22, 23, 11, 10, 9, 20,
8, 12, 25, 13, 24>, Fault input on Pin 4
Off Off Pinmap format, software assignment of all pins
Ground, +5V, and +24V power supply pins on the “D” connector should be connected with
wirewrap wire to the nearby power and ground posts H6, H7, and H8. The PLD jumpers for
these power supply pins must not be installed. Two 3K/6K resistive terminators are also
available at H5 for pulling pins up to approximately +3.3V when that is appropriate. Unused
“D” connector pins should remain both unwired and not jumpered.
Warning: It is important that the jumpers only be installed for pins that carry
TTL inputs or outputs destined for the on-board PLD. The jumpers must be
removed for all power supply pins, and for unused and reserved pins of the
external device.