Panasonic EB-GD67 Service Manual

Also see for EB-GD67: Operating instructions

TECHNICAL DESCRIPTIONMMCD020801C8 Section 4 Issue 1Service Manual – 13 – Revision 04.4.7 Real Time Clock (RTC)Clock functions are provided by a Real Time Clock built into CALYPSO. The module is synchronised by a 32.768 kHz crystaland is powered via a dedicated regulator in IOTA and is backed up by a 2.5 V button battery.CALYPSO has a clock auto compensation function to take into account any inaccuracies of the crystal. It is able to calibratecrystal tolerance / drift by writing to the compensation registers. This calibration can adjust the clock to a resolution of1 x 32768 Hz clock period.Registers for RTC are assigned between $FFFE:1800 - $FFFE:1814.4.4.8 TimersThere is a watchdog timer and two 16 bit general-purpose timers which can be used either as auto reload or one-shot timersto provide interrupts to the ARM CPU. The watchdog timer receives a 928 kHz clock signal from the CALYPSO clock module.A combination of pre-scaler and timer register gives a time range of 1.078 μs to 9.039 s. The general purpose timers receivea 812.5 kHz clock signal.4.4.9 UARTCALYPSO has two UART ports, UART modem and UART / IrDA. The UART / modem port is used for optional accessories.The UART / IrDA port is used for data connection, software debugging, factory testing and software downloading.Registers for the UARTs are located from $FFFF:5000 to $FFFF:5011 (UART / IrDA) and from $FFFF:5800 to $FFFF:5811(UART / modem).4.4.10 Accessory InterfaceThe phone uses discrete components for the buffering and level shifting at the I/O (Accessory) connector. Interfaceconnections are protected from short circuit currents up to 4.4 mA and a maximum rise time of 1.1μs.Connection of an accessory will not power up the phone.UART / MODEM PORT ASSIGNMENTCALYPSO SIGNAL PIN No. FUNCTION I/OTX_MODEM B9 UART serial data TX ORX_MODEM A9 UART serial data RX IDSR_MODEM D9 UART Data Terminal Ready IRTS_MODEM E8 UART Clear to Send OCTS_MODEM C9 UART Request to Send I