Tips for Smooth Operation of the Amigas by Bryce Nesbitt & Bruce Takahashi [Bruce's Repair (415) 525-6973] 1) For the Amiga A1000, connect the pin #10's (ground) of the four PAL's together on the daugherboard with heavy wire. Apparently the signal ground path is strange and creates unreliable logic signals to U6J, U6K, U6L, and U6N. If you want a better connection, wire the motherboard and daughter board grounds together. 2) Check the video expansion ram screws for proper length (not too long) Sometimes the screw will bend and short the second of the two layers of sheet metal to the circuit board. It may be best to try and first set the screws without the video expansion ram to "pre-tap" the sheet metal. It will be easier then to snug the hold-down screws for the expansion card. 3) Push all chips down fully into sockets. Some chips may not be seated properly or even have bent pins. Straighten bent chip pins with a pair of smooth pliers. 4) Preferences has a screen centering gadget that if moved too far to the left, will cause some of the sprites to be distorted. 5) For programmers: a) Use this instead of AllocMem(): #include "exec/memory.h" /* Safe AllocMem. Will not let your run the system down to zero bytes. * For all to use, by Bryce Nesbitt * * You may wish to increase PANIC_FACTOR. */ #define PANIC_FACTOR_CHIP 4096L APTR SafeAllocMem(size,flags) long size; long flags; { register APTR p; if ( p=(APTR)AllocMem(size, flags) ) { if ( AvailMem(MEMF_CHIP) < PANIC_FACTOR_CHIP ) { FreeMem(p,size); return(0); } /* System is low... no go! */ } return(p); } If you need to tell the user that the system is out of memory, but there is not enough memory to post a requester or Alert, simply set the title of your Window or Screen to "** NO MEMORY **" (possibly with a red pen color). This operation does not require any allocations. b) There is a bug in Text() that will clip text too soon if the write is started from beyond the left edge of the RastPort. c) WindowToFront() (and probably the other Intuition "deferred" actions) will lock up if the user is holding down an icon from the Workbench tool. 6) If you use internal memory expansion, you should ground-clip the motherboard to the internal expansion board, preferably at the point on the expansion were the ram array is. 7) Use only high quality disks. Poor disks may format and copy correctly but time may find lost data or files. 8) Make sure that your machine's fan is unobstructed and operating 9) Use a single AC power outlet with enough grounded power sockets for all your equipment. This keeps the AC polarization correct between all your equipment power supplies. If you examine a three prong outlet, you will notice that it looks like a pair of eyes with a mouth. The mouth is supposed to be electrical "ground"; the smaller slot is the "hot"; the larger slot is "neutral". A power plug without a ground prong may have one of its contact blades larger to fit only in the "neutral" slot. Don't ever defeat it's purpose. To do so will endanger you and your equipment. 10) This should have been ICHI BAN: Never connect or disconnect cables while equipment are powered, or blindly probe for a mating. This includes your printer, external drives, modems, and other peripherals. Modems, for instance, have +/- 12 volts on its pins. Damage can result when these pins accidently touch the wrong pins on the computer. Always check to see that you have the appropriate cable and cable adaptions before you attempt usage. 11) Don't guess where the cables connect. Look where you plug your equipment. The A2000 has a round DIN connector for the keyboard. Always make sure the connector marker is on top before plugging. Don't do as many people do. Don't insert and then twist until it fits. This will slowly damage your connectors. IBM PC keyboard are not compatible. 12) Be very careful that the metal band around your mouse connector doesn't short the pins of the mouse port when inserting. 13) If you encounter a power failure, turn-off all your equipment. When power is turned on by your Electric Company, your equipment may experience damaging power spikes or fluxuations. 14) Remove disks when shutting-down a system. 15) Video monitors develop high levels of static electricity. It is best to plug the monitor and computer into the power outlets before connecting the monitor cable. Always use a 3-prong power outlet. If your monitor plug wasn't designed with a ground prong, use a power outlet that is correctly polarized. 16) Always tighten the thumbscrews or clips to your connectors. 17) Never place magnets near your monitor. This includes speakers, printers, and telephones which develop magnetic energy. 18) Be sure to include in your startup-sequence file a stack command. However, programmers should check the stack size if they need more than 4000 bytes-Operating System overhead. I *don't* increase my stack, or if I do it's to 8000. 19) Before working on the interior of your computer, always touch either the disk drive's or power supply's metal casing to discharge any damaging static electricity. 20) The Amiga monitors have a metal shield installed under the casing. If you are using a non-Amiga monitor, make sure that your monitor has some shielding or make one using a metal kitchen tray (?). 21) Don't mix and blend version 1.1 stuff with 1.2 Kickstart stuff. You are asking for problems and will get them most of the time. If you are still using V1.1 Kickstart, you are asking for problems anyway. 22) When paying for shareware and you want a response from them, cut the bill in half and staple a note as to where the other half went. Nah, don't do it; it's illegal. Darn my socks! I just became a felon when I thought of an excellent programmer. 23) When plugging in cards for the A2000 Amiga, there is the end of the card which screws to the back of the Amiga. The metal bracket, which is attached to the card for this purpose, has a tendency to catch at the bottom of the bracket to the casing of the Amiga. To seat properly, the bracket must be pushed against the back of the Amiga and then it will move further down. Make sense? The main point is: Don't force the bracket to seat and especially don't use the screw to force it to seat! 24) Genlock for the Amiga may need some modifications done to sync properly. The modification needs to be done on the early models and requires that R55 resistor be removed and R108 to be changed to 1.5K ohms. R55 is a 4.7K ohm resistor located near the Q3 transistor, and R108 is a 1K ohm resistor located near pin#10 of the MC1377 chip. 25) The composite video of the Amiga A1000 needs color correction. Your red, greens, and blues may not look correct. The modification is simple; just remove resistor R140; located on the rear-left of the motherboard. On some A1000's, R140 will have to be replaced with a 470K ohm resistor instead. 26) The award for most blowable chip goes to the 8520 CIA chip. This is the interfacing chip which connects directly to your printer, modem, and external drives. It's not diode protected. Rumors leak of plans to protect it someday. This chip's demise will make your system inoperative. 27) Keep your equipment out of sunlight; even when reflected by mirror or walls while you are away from home. 28) You cannot keep your cat or dog's fur out of your internal disk drive. The fan sucks through there. 29) A clean mouse is a healthy mouse. Clean your ball and rollers with Q- Tips, rags, and toothpicks. 30) Sticky keyboard keys? Remove that key button with a chip puller and clean both button and switch with Q-Tips and alcohol. If your lucky, the shank of the key switch isn't split. If it is, The split will widen in the switch and wedge. Replace the switch. You may get lucky and find a repair station with some damaged keyboards with good switches. 31) Does your monitor seem to sink into your A1000 computer case? Put a plywood or 1/4 inch plexi-glass platform underneath. Does your A2000 keyboard seem to sink in the middle? Re-enforce the middle of the keyboard's circuit board with a rubber spacer. 32) If one or more of your mouse buttons goes flakey, it can be replaced. If the switch is "Flag", with a square body about 12mm in size with four leads you may be in luck. If the switch is the type where the actuator is completeley flush to the switch body, the replacement part can be had from Panasonic; Digi-Key (1-800-DIGI-KEY) sells it as part #P9950, 36 cents each. If the switch button is slightly raised from the main body (by about 1mm) you will either need to adapt the above part or try and find a better match. Mouser electronics (817-483-4422 or 619-49-2222) part # 10KB001, 49 cents each, *might* do the job. 33) GET VD0:!! 34) GET CONMAN 1.0 release!! 35) GET MAX HEAD ROOM (BACK)!! (More Ram; more storage; more creativity; more productivity) 36) Ribbon cables should never be bent at angles to the degree of being sharply folded. All folds of ribbon cable should gently loop. A sharp crease can damage, short or break the wires inside the ribbon cable. In the cable from the disk drive mechanism, this can mean Guru's or the device not being recognized. MANY RIBBON CABLES FOR THE BRIDGECARD HAVE BEEN DAMAGED BECAUSE OF THE CREASES IN THE PACKAGING OF THE PRODUCT. THIS HAS DAMAGED DRIVES AND BRIDGECARDS. IF A RIBBON CABLE IS SHARPLY FOLDED, USE AT YOUR OWN RISK. 37) Copy and run questionable or unknown programs from ramdisk with your disks removed or write protected. This will help to prevent you from crashing the disk drives and damaging the disks. 38) For HardDisk drive users who boot from floppy and assign WorkBench directories to hard disk: Preferences will save its system-configuration file to the DEVS: directory which was assigned to the hard drive. If you want to get preferences to save to the boot floppy, write "ASSIGN HDEV: DF0:DEVS" into the startup-sequence and then use the FILEZAP program on the Preferences program to change the ASCII letters from "DEVS:SYSTEM- CONFIGURATION" to "HDEV:SYSTEM-CONFIGURATION". 39) For A2000 users with BridgeCards, keep the ribbon cable going to the 5 1/4 floppy away from the motherboard. Lay the ribbon cable on top of the cards instead of underneath. The ribbon cable picks up interference which can cause your machine to intermittantly GURU or cause devices not to be recognized. 40) All computer equipment need a minimum amount of time before powering back online. For the Amiga A1000 and A500, you must wait a minimum of 5 seconds before power-up and as long as 30 seconds for the A2000 Amiga with the BridgeCard. Computers need time to completely power-down and discharge all voltages which may be sustaining corrupted data in RAM and other chips. 41) If your computer monitor remains powered and unattended for extended periods of time, use a display blanking program. This type of program will "black-out" your display until there is some kind of user action from the mouse or keyboard. Your display will temporarily "black-out" after a set number of minutes of inactivity. Public domain programs like "PopCLI" from the Software Distillery and "ScreenSaver" from Perry Kivolowitz are good examples. Leaving the colors stationary for days on end will burn-out the the phosphors of the monitor leaving you with a ghost image of the display forever. I set my screen to black-out after 10 minutes of inactivity.