Hardware manual

EUROCOM-17-5xx 1 Specification
Hardware Manual 5
One of the main design goals of the EUROCOM-17-5xx is efficient use of
the CPU's high speed bus. Thus, the following design rules are
established:
• Use of intelligent peripheral devices which are able to perform tasks
independent from the main CPU (NCR 53C720, CL-CD2401, ILACC).
• Independent 68020-like bus for VMEbus, Ethernet or LEB with separate
arbitration.
• Minimum interference between CPU bus, ‘020 bus and I/O bus.
• Decoupling of VMEbus and CPU bus via FIFO for BLT.
On traditional designs there could only be one bus master on the whole
board at a time. For example, if a BLT was in progress, the CPU was
blocked for the duration of the BLT. At the EUROCOM-17-5xx the CPU
bus is decoupled from the I/O bus.
The display hardware is capable of displaying up to 1152*900 pixels at a
rate of 66Hz, non-interlaced, at a dotclock of 100MHz. Smaller monitors
with 1024*768 or 640*480 non-interlaced are also supported. Every
pixel is 1/2/4/8/15/16bits wide. A color look-up table allows a selection
of 256 simultaneously displayable colors out of a palette of 16 million.
The use of video memories (VRAMs) allows immediate access to the
frame buffer, virtually independent of ongoing display activities.
An additional 512KB VRAM is implemented on the board to realize a
4-bit graphics overlay. To use the 4-bit graphics overlay, pixel width must
be programmed to 8bits.
In order to enhance system security, the EUROCOM-17-5xx incorporates
a watchdog timer. It must be retriggered periodically, otherwise the
watchdog generates a reset. After watchdog reset, the watchdog reset LED
on the front panel signals this condition. The watchdog indicator is cleared
only by power-on reset or by triggering the watchdog.
Four serial ports are located on the EUROCOM-17-5xx. One, using a
6-pin shielded RJ11 jack on the front panel, is intended for connection of a
terminal or a mouse. The other three are fed to row A and C of the
VMEbus P2 connector (X102). They can be connected via
ADAP-220/200 and CONV-300 to three 9-pin Sub-D connectors. Two of
the serial lines can be configured to support either RS232 or RS422/485
standard via SILCs (Serial Interface Level Converters).
Twelve parallel I/O-lines (X102) can be used either as centronics printer
port or as TTL-level interface (CONV-300).