W79E825A Datasheet, PDF (21/127 Pages) Winbond – 8-BIT MICROCONTROLLER

W79E825A/824A/823B/822B Data Sheet
BIT NAME
FUNCTION
This is the high byte of the standard 8052 16-bit data pointer.
7-0 DPH.[7:0]
This is the high byte of the DPTR 16-bit data pointer.
POWER CONTROL
Bit: 7
6
5
4
3
2
1
0
SMOD
SMOD0 BOF
POR
GF1
GF0
PD
IDL
Mnemonic: PCON
Address: 87h
BIT NAME
FUNCTION
7 SMOD 1: This bit doubles the serial port baud rate in mode 1, 2, and 3.
0: Framing Error Detection Disable. SCON.7 (SM0/FE) bit is used as SM0
(standard 8052 function).
6 SMOD0
1: Framing Error Detection Enable. SCON.7 (SM0/FE) bit is used to reflect as
Frame Error (FE) status flag.
5 BOF
0: Cleared by software.
1: Set automatically when a brownout reset or interrupt has occurred. Also set at
power on.
4 POR
0: Cleared by software.
1: Set automatically when a power-on reset has occurred.
3 GF1
General purpose user flags.
2 GF0
General purpose user flags.
1 PD
1: The CPU goes into the POWER DOWN mode. In this mode, all the clocks are
stopped and program execution is frozen.
0 IDL
1: The CPU goes into the IDLE mode. In this mode, the clocks CPU clock
stopped, so program execution is frozen. But the clock to the serial, timer and
interrupt blocks is not stopped, and these blocks continue operating.
TIMER CONTROL
Bit: 7
6
5
4
3
2
1
0
TF1
TR1
TF0
TR0
IE1
IT1
IE0
IT0
Mnemonic: TCON
Address: 88h
BIT NAME
FUNCTION
7 TF1
Timer 1 Overflow Flag. This bit is set when Timer 1 overflows. It is cleared
automatically when the program does a timer 1 interrupt service routine. Software
can also set or clear this bit.
6 TR1
Timer 1 Run Control. This bit is set or cleared by software to turn timer/counter on
or off.
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Publication Release Date: February 21, 2008
Revision A9