W79E201 Datasheet, PDF (29/87 Pages) Winbond – 8-BIT MICROCONTROLLER

W79E201
Accumulator
Bit:
7
6
5
4
3
2
1
0
ACC.7 ACC.6 ACC.5 ACC.4 ACC.3 ACC.2 ACC.1 ACC.0
Mnemonic: ACC
Address: E0h
ACC.7-0: The A (or ACC) register is the standard 8052 accumulator.
ADC Control Register
Bit:
7
ADC.1
6
5
ADC.0 ADCEX
4
ADCI
Mnemonic: ADCCON
3
2
1
0
ADCS AADR2 AADR1 AADR0
Address: E1h
BIT NAME
FUNCTION
7 ADC.1 Bit 1 of ADC result.
6 ADC.0 Bit 0 of ADC result.
5 ADCEX Enable external start of conversion by STADC
0 = Conversion can be started by software only (by setting ADCS)
1 = Conversion can be started by software or externally pin P2.0 (by a rising
edge on STADC)
4
ADCI ADC Interrupt flag: This ADCI flag is set when an A/D conversion result is ready
to be read. An interrupt is invoked if it is enabled. The flag may be cleared by
the interrupt service routine. While this flag is set, the ADC can not start a new
conversion. ADCI can not set by software.
3 ADCS ADC Start and Status: setting this bit starts an A/D conversion. It may be set by
software or by the external STADC signal. The ADC logic ensures that this
signal is HIGH while the ADC is busy. On completion of the conversion, ADCS
is reset immediately after the interrupt flag has been set. ADCS can not be reset
by software. A new conversion may not be started while either ADCS or ADCI is
high.
ADCI
ADCS ADC Status
0
0
ADC not busy; a conversion can be started
0
1
ADC busy; start of a new conversion is blocked
1
0
Conversion completed; start of a new conversion requires ADCI=0
1
1
Conversion completed; start of a new conversion requires ADCI=0
If ADCI is cleared by software while ADCS is set at the same time, a new A/D
conversion with the same channel number may be started.
But it is recommended to reset ADCI before ADCS is set.
2 AADR2 See the below table.
1 AADR1 See the below table.
0 AADR0 See the below table.
- 29 -
Publication Release Date: December 16, 2004
Revision A2