Chapter 2 • Local printers and other peripherals should be sited within easy reach of the ACW where they can be connected by means of interconnecting cables. 2.2.1 Rear panel connectors A range of peripherals may be connected to the rear of the ACW. A diagram of the rear panel connectors and their individual pin designation is shown in appendix E. The connectors are: (1) Composite Video output to an external monochrome or PAL colour monitor, via a BNC connector. (2) RGB output to a suitable external colour monitor. 270 degree 6-pin DIN socket. (3) RS423 standard serial interface. 5-pin domino DIN socket. The baud rate is software selectable between 75 and 9600 baud.
(4) Cassette recorder interface. 270 degree DIN socket. Standard CUTS tones are used at 300 or 1200 baud. (5) Analogue interface providing four 8-bit ADC input channels capable of reading analogue voltages in the range 0 to 2.5V. The conversion time is 10mS. A 1.8V reference voltage is also available on the pins of the 15- way D-type female connector. (6) ECONET network connector. 180 degree 5-pin DIN socket. (7) Keyboard socket. 25-pin D-type female connector. (8) Printer 8-bit parallel port (Centronics standard). 24-way DELTA IDC connector. (9) 1MHz BUS 37-way D-type female connector. (10) Mouse interface socket (optional) 9 Way D-type.
WARNING It is possible to plug the ECONET system into the CASSETTE socket. This will not harm either the ECONET or the ACW but the entire ECONET system will be rendered inoperative until the error is rectified. 2.3 Disassembly and re-assembly 2.3.1 Safety considerations WARNING — HIGH VOLTAGE HAZARD The ACW's video monitor generates potentially dangerous high voltages. These voltages can remain within the monitor circuits for several hours after the mains supply has been disconnected. OBSERVE FULL SAFETY PRECAUTIONS WHENEVER THE UPPER PLASTIC CASE OF THE ACW HAS BEEN REMOVED. DISCONNECT THE ACW AND ALL PERIPHERAL EQUIPMENT FROM THE MAINS SUPPLY.
UNDER NO CIRCUMSTANCES SHOULD AN UNCASED MACHINE BE LEFT UNATTENDED IN THE PRESENCE OF UNQUALIFIED PERSONNEL. When working on the ACW it is important to ensure that the surrounding surfaces are dry and isolated from earth. Avoid contact with any metal objects which may be earthed, such as piping or heating equipment. 12 ACW SERVICE MANUAL Issue 1