W77C58 Datasheet, PDF (10/71 Pages) Winbond – 8 BIT MICROCONTROLLER

Preliminary W77C58
instructions that use DPTR will now access DPL1 and DPH1 in place of DPL and DPH. If they are not
required, the user can use them as conventional register locations.
Data Pointer Select
Bit:
7
6
5
4
3
2
1
0
-
-
-
-
-
-
- DPS.0
Mnemonic: DPS
Address: 86h
DPS.0: This bit is used to select the DPL,DPH pair or the DPL1,DPH1 pair as the active Data Pointer.
When set to 1, DPL1,DPH1 will be selected, otherwise DPL,DPH will be selected.
DPS.1-7: These bits are reserved, but will read 0.
Power Control
Bit:
7
6
5
SM0D SMOD0 -
4
3
2
1
0
-
GF1 GF0 PD IDL
Mnemonic: PCON
Address: 87h
SMOD : This bit doubles the serial port baud rate in mode 1, 2, and 3 when set to 1.
SMOD0: Framing Error Detection Enable: When SMOD0 is set to 1, then SCON.7(SCON1.7)
indicates a Frame Error and acts as the FE(FE_1) flag. When SMOD0 is 0, then
SCON.7(SCON1.7) acts as per the standard 8052 function.
GF1-0: These two bits are general-purpose user flags.
PD: Setting this bit causes the W77C58 to go into the POWER DOWN mode. In this mode all the
clocks are stopped and program execution is frozen.
IDL: Setting this bit causes the W77C58 to go into the IDLE mode. In this mode the clocks to the
CPU are 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
IT
IE0
IT
Mnemonic: TCON
Address: 88h
TF1:
TR1:
TF0:
TR0:
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.
Timer 1 runs control: This bit is set or cleared by software to turn timer/counter on or off.
Timer 0 overflow flag: This bit is set when Timer 0 overflows. It is cleared automatically when
the program does a timer 0 interrupt service routine. Software can also set or clear this bit.
Timer 0 runs control: This bit is set or cleared by software to turn timer/counter on or off.
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