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boards:s100:backplanev4:historical [2017/01/09 22:54] admin |
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| - | ====== Historical S-100 Backplane V2/V3 - 8-slot ====== | + | ====== Historical S-100 Backplane |
| + | {{: | ||
| - | ===== Build Instructions ===== | + | <note important> |
| - | ====== | + | |
| - | (from N8VEM wiki, by Don Caprio) | + | ===== S-100 Backplane Build Notes by Don Caprio===== |
| - | + | ==== Step 1 ==== | |
| - | ===== Step 1 ===== | + | |
| Gather the parts. I use Jameco, Digi-key and Mouser. Unfortunately one source does not have all the parts. I had to place orders at both sources to get all the parts needed. Primary source was Jameco and whatever they did not carry I used Digi-Key. The downside of ordering resistors at Jameco is you have to order in quantities of 100. | Gather the parts. I use Jameco, Digi-key and Mouser. Unfortunately one source does not have all the parts. I had to place orders at both sources to get all the parts needed. Primary source was Jameco and whatever they did not carry I used Digi-Key. The downside of ordering resistors at Jameco is you have to order in quantities of 100. | ||
| Line 14: | Line 13: | ||
| Note: Digi-Key carries everything for this project except the resettable fuses. | Note: Digi-Key carries everything for this project except the resettable fuses. | ||
| - | [[DigiKey_S100_bom.txt]] <- Digi-Key BOM with S100 edge connectors | + | {{: |
| - | [[DigiKey_S100_withoutEdgeCon_bom.txt]] <- Digi-Key without edge connectors. | + | {{: |
| As of Jan 2011 the parts with S100 connectors runs about $149, and $24.00 without S-100 female connectors. | As of Jan 2011 the parts with S100 connectors runs about $149, and $24.00 without S-100 female connectors. | ||
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| Anchor Electronics has the S100 connectors for $3.95 each, not as nice, but still very serviceable. | Anchor Electronics has the S100 connectors for $3.95 each, not as nice, but still very serviceable. | ||
| - | ===== Step 2 ===== | + | ==== Step 2 ==== |
| Get your magnifying glass out and inspect the PCB board. Your are looking for any solder bridges or holes that may have gotten filled by the solder mask. | Get your magnifying glass out and inspect the PCB board. Your are looking for any solder bridges or holes that may have gotten filled by the solder mask. | ||
| - | ===== Step 3 ===== | + | ==== Step 3 ==== |
| This may seem like an un-needed step but I can assure you it is well worth it. Inspect the parts that you received very closely. Just because the packaging says it's a specific part it may not be. Errors happen. Installing the incorrect components could result in your project not working which may take hours and hours to fix. Take your time and double check the component when mounting it in the PCB. The extra time is well worth it. | This may seem like an un-needed step but I can assure you it is well worth it. Inspect the parts that you received very closely. Just because the packaging says it's a specific part it may not be. Errors happen. Installing the incorrect components could result in your project not working which may take hours and hours to fix. Take your time and double check the component when mounting it in the PCB. The extra time is well worth it. | ||
| - | ===== FAQ ===== | + | ==== FAQ ==== |
| - | ==== Calibrating the Trimmer POT ==== | + | === Calibrating the Trimmer POT === |
| The trimmer pot is used to calibrate the active terminator circuit. Basically you set the pot at mid setting and then power up the circuit. Use your VOM to measure the voltage on the signal pins and adjust the pot so they settle at 2.65V to 2.7V. That is dead center of the TTL “no mans land” between high and low. The active terminator keeps all the signals solidly there until a bus buffer/ | The trimmer pot is used to calibrate the active terminator circuit. Basically you set the pot at mid setting and then power up the circuit. Use your VOM to measure the voltage on the signal pins and adjust the pot so they settle at 2.65V to 2.7V. That is dead center of the TTL “no mans land” between high and low. The active terminator keeps all the signals solidly there until a bus buffer/ | ||
| - | ==== What are The P2, P3, P4 and P5 Headers used for? ==== | + | === What are The P2, P3, P4 and P5 Headers used for? === |
| Those connectors are for the “to be announced” ECB to S-100 bridge board. Once that is done it will allow N8VEM ECB systems to expand to S-100 and vice versa. Until the PCB is done though I would not fill the connectors since it is going to be a while. | Those connectors are for the “to be announced” ECB to S-100 bridge board. Once that is done it will allow N8VEM ECB systems to expand to S-100 and vice versa. Until the PCB is done though I would not fill the connectors since it is going to be a while. | ||
| - | ==== What are The JP1, JP2, and JP3 jumpers for? ==== | + | === What are The JP1, JP2, and JP3 jumpers for? === |
| These correspond to the IEEE-696 ground pins. Some boards require them and other boards use them for different signals. The early S-100 boards are not fully IEEE-696 standard compliant. You can see these jumpers on the various S-100 boards on the left hand side near the edge connector. | These correspond to the IEEE-696 ground pins. Some boards require them and other boards use them for different signals. The early S-100 boards are not fully IEEE-696 standard compliant. You can see these jumpers on the various S-100 boards on the left hand side near the edge connector. | ||
| - | ==== P12 ==== | + | === P12 === |
| This is for an external reset switch. | This is for an external reset switch. | ||
| - | ==== How do I orient the LED pins? ==== | + | === How do I orient the LED pins? === |
| The pin 1 of LEDs is square. That’s true for all parts so you can easily identify pin #1. You can pick the LED orientation off the schematic once you know pin #1 location. The bar on the LED symbol matches the flat part on the LED so that is also helpful. | The pin 1 of LEDs is square. That’s true for all parts so you can easily identify pin #1. You can pick the LED orientation off the schematic once you know pin #1 location. The bar on the LED symbol matches the flat part on the LED so that is also helpful. | ||
| - | ==== How do the terminating resistor packs go? ==== | + | ===== S-100 Backplane Improvements & Fixes ===== |
| + | <note important> | ||
| + | < | ||
| + | Fixes: | ||
| + | 1. re-work fuses to current limit the boards | ||
| + | 2. Fix Q1 transistor orientation. Involves a 180 degree rotation. | ||
| + | |||
| + | Improvements: | ||
| + | 1. add pin notations to silkscreen for pin 1 and board orientation | ||
| + | |||
| + | More notes: | ||
| + | |||
| + | Bob Bell: | ||
| + | The power connector is easy if you use the terminal blocks like those found in the current Jameco catalog page 63. | ||
| + | They " | ||
| + | 1. Board thickness needs to be reduced. | ||
| + | 2. One of the transistors has it's silk-screen mirrored. | ||
| + | 3. The fuses are only protecting the LEDs. | ||
| + | 4. The 0.3" lead-to-lead pitch on the 1/4 Watt resistors is too narrow. | ||
| + | 5. The schematics are rather difficult to follow. | ||
| - | Each set of 19 holes have 2 x 9-pin resistor packs, inserted like so: | + | Jeff Albrecht notes: |
| + | Add holes to make board directly fit into ALTAIR & IMSAI Chassis. | ||
| - | < | + | Josh Bensadon notes: |
| - | _________________ | + | -Add edgecard pads or headers to make boards stack up in tandem (after note by Curt Mayer for an 18 slot) |
| - | | | | | | | | | | o | | | | | | | | | | + | -Perhaps include 2 types of power connectors? |
| - | ^ | + | </file> |
| - | pin 1 pin 1^ | + | |
| - | </code> | + | |
| ===== Photo Gallery ===== | ===== Photo Gallery ===== | ||
