ECBbus 3 U Series 20

The ECB system bus is an 8-bit parallel bus designed for the Z80 microprocessor family. Since there is no DIN/IEC/IEEE/... specification for the ECBbus, several ECBbus pin assignments are on the market. The pin assignment of the Hartmann ECBbus matches the Kontron ECB assignment. Thanks to its special layout design and the large number of different power supply potentials, the Hartmann ECBbus is suitable for universal use, including customer-specific applications.

All Hartmann ECBbus boards are based on the HIGH SPEED DESIGN concept. Low reflection is achieved by means of uniform characteristic impedance for all signal lines.

Shielding of each individual signal line and twisted pair construction assure minimal inductive and capacitive coupling and therefore guarantee trouble-free operation even at elevated data transfer rates.

Variants for wiring daisy chain interrupt and bus priority control

• Variant A
  The interrupt and bus priority chains can be switched from slot 1 to the next slot with 0.4“ jumpers.
  An additional 0.1” jumper can be used to bridge an unused slot.
  The jumpers can be inserted in pressfitted precision contacts.
• Variant B
  The pins 11C (IE IN), 16C (IE OUT), 12A (BA IN) and 17A (BA OUT) are executed as gold-plated 0.6 x 0.6 mm wire-wrap posts for user wiring.
  This permits forward and backward wiring in any sequence.

Noise-free power supply

Thick power supply lines guarantee minimal voltage drops on the bus board. Additional terminal bars can be used to significantly reduce the voltage drop, particularly in conjunction with extremely high loads (+5 V: > 30 A, GND: > 50 A).

Dynamic parasitic voltages in the system can be reduced by installing blocking capacitors. Several contact spacings for the blocking capacitors are provided.

Power and sense connections are established via soldered Faston quickconnect terminals.

Termination

The first and last slots on the bus boards of variants A and B are prepared for terminator boards. A shroud is preinstalled in these slots.

Since the terminator board is plugged in on the back side of the bus board, no slot is lost. All signal lines (V1) on the terminator board are connected to pull-up/pull-down resistor networks.