Jumper Configurations
Table A-1
Jumper Descriptions (continued).
JUMPER #
DESCRIPTION
W12
Install jumper W12 to bring battery ground
reference to the timekeeper and 32 Kbyte
RAM, and any other RAM chosen for battery
backup by jumpers W35 and W38. Remove
this jumper to erase the RAM (the RAM
drive for DOS systems) and timekeeper. For
rapid erasure of RAM and timekeeper while
W12 is removed, temporarily short the W12
pin nearest the extractor to STD bus ground
pins 3 and 4. Factory default installs W12.
Note: If the battery is not installed, ensure proper
operation of timekeeper and 32K static RAM by
installing a wire across the (+) and one of the (-)
terminals of the battery sockets, and install W12.
To clear battery-backed RAM, quickly remove
jumper W12 and tie top pin of W12 to ground pin
of pack 1B (8254 counter/timer) for a second or
two, then replace jumper W12.
W12
Function
IN †
Tie the battery output to the time-
keeper and all battery-backed RAM
OUT
Erase the timekeeper and all battery-
backed RAM
A-10
Содержание ZT 8809A
Страница 15: ...Tables Table B 9 J5 Pin Assignments B 17 Table B 10 J6 Pin Assignments B 18 Table B 11 J7 Pin Assignments B 19...
Страница 334: ...Jumper Configurations W49 W48 A W47 B A B W37 W66 A W50 B C J7 W67 Figure A 11 W37 W47 50 W66 W67 Jumper Blocks A 34...
Страница 346: ...Jumper Configurations W61 W60 W62 W63 W64 A B A B W65 Figure A 13 W60 W65 Jumper Block A 46...