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Rockbox mail archiveSubject: Re: recorder schematics (differences)Re: recorder schematics (differences)
From: Joachim Schiffer <gemoin_at_gmx.net>
Date: Wed, 19 Dec 2001 19:26:11 +0100 > If i manage to define the needed devices in eagle, I try to draw a > schematic of the things I discovered so far, so that we have a schematic > of the player and the recorder. There are only a few parts left to trace :) The "TM41ST84W" is indeed a realtime clock, which has also built-in watchdog-functions, and is controlled by I2C Bus at Pins PB7 (SDA) and PB13 (SCL) It will take a few days, until i can post the (almost) complete schematic of the recorder, because i have to define all devices except Opamps and ttl-ics... Until then, i can post single connections if they were important to analyze the firmware code... The most important might be these (i think): CPU meaning =========== PB10 serial in (remote control) PB6 red led PB8 on button (pulled low if pressed) PA5 power on hdd AN6 battery voltage (over FET, switched) AN2 battery voltage (directly connected over diode) AN0 must be an output... goes to a voltage divider and then to a comparator with 2 or 2,5 volt reference diode... if the output of this comparator goes low, the off-switch is activated (i think this is used, if the battery gets low, to stop the player) the reference voltage is also connected to PB5 Powers on internal power_supply which is connected to the external supply... (at this point it's getting dangerous, i think... please use at your on risk ;) If this supply is powered on, the battery gets loaded. If the battery is full, the supply is switched off, and the recorder unloy runs from battery. AN1 is connected to PB 5 (dont know why) PB4 off button (pulled low if pressed) if PB4 is switched to low, the unit will probably switch off, too. Also the output of the voltage comparator is connected to this pin. (stops playing if power fails) PB7 SDA (for Micronas and RTC) PB13 SCL (for Micronas and RTC) AN11 Buttons UP, F3 (right), F2 (middle), F1 (left) AN13 Buttons PLAY, DOWN, RIGHT, LEFT /* AN11, AN13: buttons ordered by their voltage from low (1,1V?) to high (1,6V?) */ /Joachim Received on 2001-12-19 Page template was last modified "Tue Sep 7 00:00:02 2021" The Rockbox Crew -- Privacy Policy |