MiniSport Laptop Hacker - Vol 11, 5 Apr 1993 Copyright(C) 1993 by Brian Mork. >>> CONSERVING ENERGY Your MiniSport runs on NiCad batteries. It is good to regularly let these run down until you get the red POWER light flashing and beeping. That deals with the well-known "memory" effect of NiCads. However, if you let the NiCads stay in this discharged state, the Lithium batteries ($2 each, CR2430, RS 23-166) will go dead *fast*. The NiCads, even fully charged, will eventually be discharged from backing up the RAMdisk. From experi- ence, I know that 2 months of inactivity will fully discharge both the RAM- disk and the Lithium batteries. There are a lot of power management techniques specific to the MiniSport, and that's what the rest of this section will be about. The effect of choosing the lower-power option on each of the following independent areas is cummulative. By managing my batter energy, I regularly get 4-plus hours of "on" time before the power light starts blinking. That's 4 hours in my work room, not in the manufacturer's literature! 1) The mechanical movement of the floppy drive is by far the worst power draining activity. Limit it's acitivy to the minimum possible. I use my floppy drive to back up an afternoon's worth of work, not to perform that work. Each time the floppy drive is accessed, picture 5-10 minutes of NiCad charge going away. 2) When you're not using the computer, turn it off! The computer only takes a few seconds to boot up from a power-off state. If you're look- ing up some documentation or twiddling some knobs on other equipment for more than a minute or two, there is little reason to leave it on. Turn- ing off your computer as you step away from the desk is a practice you'll have to get used to. 3) Turn your screen to minimum brightness. If you're in a bright room or sunlight, you may get by with the brightness turned all the way down. In the SETUP menu (CTRL-ALT-INS, or ESC during bootup) you can set a timer to automatically turn the screen off after a few minutes. Set the timer to the minimum value. 4) The I/O ports (COM1, COM2, LPT1) can each be "turned off" even while the computer is turned on. Once again, check the SETUP menu or use the MA- CHINE command at the DOS command prompt. If you won't use the ports for the next few hours, turn them off! 5) The MiniSport can be set to execute instructions at a fast speed or a slow speed. The cost of running at fast speed is greater use of energy. For a portable, that means less battery life. Again, use the MACHINE command or the SETUP menu to choose the SLOW speed unless you need the fast speed. If you do select the FAST speed, the biggest waste of energy occurs when the computer makes an I/O request to the disks. It's silly to let the computer do nothing very fast while it waits for the disk! Zenith recognized this and provided a SMART option for the clock speed. With this setting, the computer runs at FAST except during disk I/O, at which time it automatically goes into the SLOW mode. One last thought: there's a third, even easier, way to switch between the speed settings. The SLOW and FAST selections on the F3 and F4 key provide this exact function. Use SETUP to choose the slow speed and then only if you need it, press the FN-F4 (fast) key. Because it's so easily available, I select SLOW at the SETUP menu and choose FAST from the keyboard only if I feel I need it. 6) Keeping the RAMdisk saved when power is off uses energy, but because I use it like a small hard disk, I accept that sacrifice. If you're look- ing for maximum time between recharges, USE the SEUP menu to select not to keep the RAMdisk saved. 73, Brian Mork (Opus-OVH) KA9SNF@wb7nnf.#spokn.wa.usa Internet ka9snf@jupiter.spk.wa.us 6006-B Eaker, Fairchild, WA 99011