fdb@mgweed.UUCP (03/30/85)
where does pin 12 of IC U8 go ? I tried to trace it with an ohm meter but it goes off into the wild blue younder. I just put a switch between 1 and 3 of cn2 (user port),if this is not the same someone please let me know.
jose@utcs.UUCP (Jose Antonio Dias) (04/06/85)
In article <16185@mgweed.UUCP> fdb@mgweed.UUCP writes: > > where does pin 12 of IC U8 go ? >I tried to trace it with an ohm meter but it goes >off into the wild blue younder. Look in the schematic diagram of the 64 on the bottom right hand corner of the front page of the diagram. There you will find that pin 12, one output of a 7406 (u8) splits to 2 places. The first is a 1k resistor, r36, that is connected to the +5v source. The second joins the RESET line that goes to the IN pin on the 6510a MPU (u7). The RESET line continues on the other side and goes to the sid chip, the 6581 (u18). You should be able to get the info from the Programmer's Reference Guide, but if you cann't get a copy of it then send me a request for a photo- copy and we'll work something out. > I just put a switch between 1 and 3 of >cn2 (user port),if this is not the same someone please >let me know. I do something like that, but you should be carefull and place a diode on the line to prevent any stray spikes from "flowing backup your power supply." A momentary switch would also be a good idea since you don't want the RESET line low too long, just long enough... -- Jose A. Dias University of Toronto Computing Services ------------------------------------------------------------------------------- The above ascii characters are not, have not ever been, or will ever be, the opinion of anybody, being, or super-intelligent shade of the colour blue. They were just a fluke. They were put together by randomnly selecting phrases from Vogon poetry... ------------------------------------------------------------------------------- uucp: {decvax,ihnp4,utcsri,{allegra,linus}!utzoo}!utcs!jose bitnet: JOSE@UTORONTO 300/1200: (416)535-5360 (As the crow flies... :-)