H-Clk and MEZ-456 Access Connector Cables --------------------------------- Original Rev: 13-FEB-2012 Current Rev: 27-July-2012 This file describes all of the cables that may/will be used with the Access Connectors on both the H-Clk and MEZ-456 cards. Both the H-Clk and MEZ-456 cards have a 40 pin 2mm 2x20 connector that is used to access points on the card that are not available through the normal front-panel or mid-card connectors. The Access connector headers themselves are: Molex Part No. 87832-4020 Digi-Key Part No. WM18648-ND price $3.50 ea Project Part No. Connector_2x20 The housings and contacts that are used top plug into these Access headers are: Housing Waldom 51110-2050 Contacts Waldom 50394-8100 An alternative 40 position housing and contacts are: Housing 40 position with key: FCI No 90311-040LF Contacts FCI No 77138-001LF 1. H-Clk Front-Panel Push Button to cause FPGA Configuration Cable Cable to connect the Normal Open contact of the recessed switch S2 i.e. the Configure Pushbutton on the H-Clk card to the PROG_B signal on the MEZ-456 card. H-Clk Signal MEZ-456 Signal ------- ---------- --------- ---------- J5-38 S2 N.O. J5-14 PROG_B J5-39 Ground J5-11 Ground 2. Initial MEZ-456 stand-alone test cable Cable to make some initial stand-alone tests of the MEZ-456 card. The stand-alone tests of the MEZ-456 card use the H-Firm_1 firmware. These tests include: - Demonstrating that one can program firmware into the Configuration PROM on the MEZ-456 card - Demonstrating that one can then cause the FPGA on the MEZ-456 card to Configure. - Finally "running" the H-Firm-1 firmware by demonstrating that one can turn ON and OFF 2 LEDs with a switch. Both the switch and the LEDs are tied to spare FPGA normal I/O pins that have been routed to the MEZ-456 Access Connector. MEZ-456 Signal Connects to on this Cable Assembly --------- ---------- ------------------------------------ J5-14 PROG_B J5-13 and J5-14 are connected to J5-13 Ground a Normal Open pushbutton. Pushing will cause the FPGA to Configure. J5-26 IO_L93P_6 J5-26 is tied to the center contact on a SPDT switch. One of the outer J5-25 Ground contacts is tied to Ground via J5-25. The other outer contact ties to Vdd +3.3 Volts through a 1000 Ohm resistor. J5-28 IO_L94P_4 J5-28 ties to 560 Ohm resistor and then to the Cathode of an LED. The Anode of the LED goes to Vdd +3.3V. ON when SW Hi. J5-30 IO_L94N_4_VREF_4 J5-30 ties to 560 Ohm resistor and then to the Cathode of an LED. The Anode of the LED goes to Vdd +3.3V. ON when SW Low. 3. Monitor the Clocks and PLL A cable to allow monitoring of the 10 MHz reference signal from the GPS Receiver, the 40 MHz clock from the Quartz PLL, and monitor the PLL's feedback loop is described in the following table. Note that monitoring of the 10 MHz and 40 MHz signals with the setup described in this table requires the MEZ-456 firmware to deliver copies of these clocks on the specified pins. H-Clk Signal ------- --------------------------------------------------- J5-30 DEBUG_06 copy of the 10 MHz GPS reference clock J5-34 DEBUG_08 copy of the 40 MHz PLL clock J5-25, J5-29, J5-33, J5-37 Grounds for above measurement J5-16 PLL Loop Monitor Point analog voltage 0V to +5V J5-13, J5-15, J5-17 Grounds for above measurement 4. Provide the 40 MHz Clock to one H-Clk card from another H-Clk card A typical application of this is to provide the 40 MHz Clock to a Control type H-Clk card from a Clock type H-Clk card. Both of these H-Clk cards are in the same VME crate and they work together to provide both the GPS Timestamp and the TDC Control functions to the HAWC experiment. They run from a common 40 MHz clock source provided by the Clock type H-Clk card. There is an 8 pin cable to cable connector in the middle of this setup so that the cable from the Clock type H-Clk card is not permanently attached to the cable from the Control type H-Clk card. In the following table the type of contact that is used at each location on this 8 pin cable connector is indicated with m or f. Pin Numbers on Access Connectors or Cable Connectors ----------------------------------------------------------- Clock Control Type Clock Clock Control Control Type H-Clk Type Type Type Type H-Clk Card H-Clk Cable Cable H-Clk Card Function MEZ-456 Card Connector Connector Card MEZ-456 -------- ------- ----- --------- --------- ------- ------- Configure S2 N.O. to 14 38 38 14 PROG_B Ground 11 39 39 11 for above Grounds 1 1 m 1 f 1 2 2 m 2 f 2 40 MHz Dir 4 3 m 3 f 10 Out --> In 40 MHz Cmp 6 4 m 4 f 12 Out --> In Grounds 7 5 m 5 f 7 8 6 m 6 f 8 Grounds 13 7 f 7 m 13 14 8 f 8 m 14 Looking at the pin side of the 8 pin connector on the cable to the card that is sourcing the 40 MHz clock signal the layout is: 1 Gnd 3 40 MHz Dir 5 Gnd 7 Gnd Blk M Red M Blk M Blk F 2 Gnd 4 40 MHz Cmp 6 Gnd 8 Gnd Blk M Grn M Blk M Blk F The H-Clk card that will receive the External 40 MHz clock signal (typically a Control type H-Clk card) must be setup to accept and distribute the External clock signal. On the card that will operate from an External clock, remove jumpers R252 and R253, and install jumpers R254 and R255. Also install a 100 or 110 Ohm resistor across the U251 terminals of jumpers R252 and R253. This resistor is to terminate the unused output of U251 (this card's locally generatied 40 MHz) which is the now unused because this card is running from an External Clock. Mark the card and indicate in its inventory sheet that these jumpers have been setup for this H-Clk card to use an External clock.