Philips P89LPC920 User Manual page 4

Philips Semiconductors
Mode 0..................................................................................................................... 42
Mode 1..................................................................................................................... 42
Mode 2..................................................................................................................... 43
Mode 3..................................................................................................................... 43
Mode 6..................................................................................................................... 43
Timer overflow toggle output ................................................................................... 46
8. Real-Time Clock/System Timer................................................................. 47
Real-time Clock source ........................................................................................... 47
Changing RTCS1-0 ................................................................................................. 47
Real-time Clock interrupt/wake up........................................................................... 48
Reset sources affecting the Real-time Clock........................................................... 48
9. UART......................................................................................................... 51
Mode 0..................................................................................................................... 51
Mode 1..................................................................................................................... 51
Mode 2..................................................................................................................... 51
Mode 3..................................................................................................................... 51
SFR space............................................................................................................... 51
Baud Rate Generator and selection ........................................................................ 52
Updating the BRGR1 and BRGR0 SFRs ................................................................ 52
Framing Error .......................................................................................................... 53
Break Detect............................................................................................................ 53
More about UART Mode 0....................................................................................... 55
More about UART Mode 1....................................................................................... 56
More about UART Modes 2 and 3........................................................................... 57
Framing Error and RI in Modes 2 and 3 with SM2 = 1 ............................................ 57
Break Detect............................................................................................................ 57
Double buffering ...................................................................................................... 58
Double buffering in different modes......................................................................... 58
Transmit interrupts with double buffering enabled (Modes 1, 2 and 3) ................... 58
The 9th bit (bit 8) in double buffering (Modes 1, 2 and 3)........................................ 59
Multiprocessor communications .............................................................................. 60
Automatic address recognition ................................................................................ 60
10. I2C interface ............................................................................................ 63
I2C Data register ..................................................................................................... 64
I2C Slave Address register...................................................................................... 64
I2C Control register ................................................................................................. 64
I2C Status register................................................................................................... 66
I2C SCL Duty Cycle registers I2SCLH and I2SCLL ................................................ 66
I2C operation mode ................................................................................................. 67
Master Transmitter Mode.............................................................................. 67
Master Receiver Mode.................................................................................. 68
Slave Receiver Mode.................................................................................... 69
Slave Transmitter Mode................................................................................ 69
11. Analog comparators ................................................................................ 79
2003 Dec 8
4
User Manual - Subject to Change
P89LPC920/921/922