Hardware manual

1 Specification EUROCOM-17-5xx
14 Hardware Manual
1.3.10 Parallel I/O There is one 8-bit parallel port with handshake signals on the
EUROCOM-17-5xx. This parallel port is based on a Zilog Z8536 device
(user CIO). The port signals are routed via the VMEbus P2 connector and
the ADAP-220/200 to the CONV-300 board. Three 9-pin Sub-D serial
plugs, a 25-pin Sub-D parallel connector (Centronics printer interface) and
a 26-pin connector for direct access to the CIO pins are installed on the
CONV-300.
The I/O ports of the user CIO features programmable polarity,
programmable direction (bit mode), pulse generators, and programmable
open drain outputs. Four handshake modes, including 3-wire (like
IEEE-488), are selectable. The CIO is also programmable as a 16-vector
interrupt controller.
1.3.11 CIO Counters/
Timers
The EUROCOM-17-5xx offers three independent, programmable 16-bit
counters/timers integrated in the user CIO. They can be used as general-
purpose devices with up to four external access lines per counter/timer
(count input, output, gate, and trigger). Port A and port C lines of the user
CIO are routed to a 26-pin I/O connector on the CONV-300 for user
applications.
1.3.12 Parameter
RAM and Real-
Time Clock
The real-time clock is designed with the MK48T12 timekeeper RAM. It
combines a 2KBx8 CMOS SRAM (parameter RAM), a bytewide
accessible real-time clock, a crystal, and a long-life lithium battery, all in
one package. Alternatively, a MK48T18 device can be used which offers
8KB SRAM or a DS1644 device which offers 32Kx8KB SRAM.
1.3.13 Revision
EEPROM
The revision EEPROM is realized by a 512x8B serial EEPROM which
offers special board revision information. The lower half size of the
EEPROM is programmed by ELTEC and should not be modified by the
user to guarantee board revision consistency. The upper 256B can be used
by the user to store additional information.
1.3.14 VIC Timer The VIC contains a timer which can be programmed to output a periodic
wave form on LIRQ2. The available frequencies are 50Hz, 100Hz, and
1000Hz. The VIC timer is typically used as a tick timer for multi-tasking
operating systems.