|Hardware articles index > Thrumpcard|
Designed by Innovonics to overcome the Aces edge connector lay out. By wiring the trumpcard to the ZX81 layout will allow you to use ZX81 peripherals with the Ace.
Trumpcard 22 pin Edge connector
INNOVONICS TRUMFCARD - INSTRUCTIONS
Trumpcard was originally designed as a mechanical and electrical link between the Jupiter Ace and ZX peripherals. To maintain flexibility and programmability the two connecting edges are quite separate. In this way the constructor can colour code and interrupt the signal lines as he pleases, both for experimental and permanent applications.
With the exception of the chip select lines, WE on the ACE and RAM/ROM CS. on the ZX 81, both computers share the same bus albeit in a different configuration.
STANDARD CONSTRUCTION - GENERAL PURPOSE, ALL LINES CONNECTED
Trumpcard topside - Side A has the ZX polarizing slot at top left. Side B is underside.
1. Bend connector pins outwards at their midpoint approx. 30°
2. Bend pins back to centre at their base, such that pinends leave just enough room to accept the Trumpcard PCB.
3. Ensuring pin ends are flat against PCB tracks, insert card and align right ' most pins ( adjacent to connector polarising key ) with Track 2 Side A.
0.6 mm single core connecting wire is recommended. Multi core wire is prone to causing shorts after soldering but can be used if necessary. If thin telephone wire is used, all lines can be routed through holes, otherwise construct as per instructions below.
1. Slide connector pins approx. 3 mm over PCB tracks on the un slotted edge of the card leaving sufficient room to solder connecting wires. Check that the top row of pins is well clear of the bottom row, particularly at their bending point.
2. Taking care that the card lies parallel to connector body, tack solder the outermost pins on both sides to the PCB. This facilitates the soldering of the remaining pins, which should be held flush to the PCB tracks for a neater finish. 3. Prepare interconnection wires by paring off 3 mm insulation at both ends.
4. Following the interconnection tables, assemble the underside first, starting at ACE 2B and working thru to 22B. 15B to 19B will need to be threaded under some of the control lines, in order to work through the tracks consecutively.
Leave at least 4mm of track free on the ZX side to allow the peripheral to seat properly when applied.
5. Turn the assembly over, soldering from ACE 23A to 3A consecutively. Only 10T passes through a hole. Thread the remaining wires between connector body and PCB over its edge to side B.
N.B. Check your connections and inspect work for solder splashes.
TAKE PARTICULAR CARE TO CONNECT THE 9V LINE ACE 21A/ZX 22B CORRECTLY.
TTL chips carry a maximum 7V0 rating !!
Having checked your wiring thoroughly, attach your peripheral to the card, then holding the card attach it to the ACE's Expansion port. Ensure both peripheral and ACE are on a stable flat surface. N.B. The ACE PCB polarising slot is slightly wider than the connector key itself. With the keyboard facing you and Trumpcard attached, push the connector firmly to the right of the slot - you may hear it click home. Check this point, as a perfectly wired card may not function if connector pins and ACE PCB tracks are slightly misaligned. Screen white-outs or a scrolling cursor indicate a poor or wrong connection.
I/O boards, D/A's, A/D's etc will require homegrown software to test them.
RAMpacks of 16, 32, and 64K will return unsigned RAMTOPS of 32768, 49152 and 65536 ( screen display -32768, -16384, 0 respectively ) by typing 15384 @ . which is the ACE's RAMTOP system variable. If the machine crashes, switch off, make necessary adjustments and switch on again. Unless the 9V line is wrongly connected, it is very unlikely that either the ACE or your peripheral is damaged. Check your assembly closely and all should be well.
ALTERNATIVE APPLICATIONS Trumpcard need not be used only on the ACE, similarly, the ZX tracks can be used to attach other types of connectors. E.G. Ribbon cable 0.05 and 0.1 pitch/ PCB header pins straight or right-angled on 0.1 centres/ wire wrap DIL sockets 0.3" and 0.6". Even 'D' Type subminiature Sockets/Plugs with solder bucket connectors will slip snugly over the PCB edge. The buckets themselves will have to be wired separately - they are not on the same pitch as the PCB tracks.
WIRING TABLE A = Topside B = Underside
|ACE||Wire Length||ZX Route||Signal||ACE||Wire Length||ZX Route||Signal|
|6A||2¼"||5B Edge||A7||4B||2"||13A H3||HALT|
|7A||2¼"||6B Edge||A8||5B||2"||14A H3||MREQ|
|8A||2¼"||7B Edge||A9||6B||2"||15A H3||IORQ|
|9A||2¼"||8B Edge||A10||7B||2"||16A H3||RD|
|10A||2"||15B H2||A2||8B||2"||17A H3||WR|
|14A||2¼"||13B Edge||A15||12B||2"||21A H3||RESET|
|15A||2¼"||12B Edge||A14||13B||2"||22A H3||M1|
|16A||2¼"||11B Edge||A13||14B||2"||23A H3||RFSH|
|Hole 1 is at left when card in viewed from top.
Trumpcard numbering system is independent of any ZX81 convention.