p89lpc904 NXP Semiconductors, p89lpc904 Datasheet - Page 18

• Manufacturer Part Number: p89lpc904
• Description: 8-bit Microcontrollers With Two-clock Accelerated 80c51 Core 1 Kb 3 V Byte-erasable Flash With 8-bit A/d Converter
• Manufacturer: NXP Semiconductors

Philips Semiconductors
9397 750 13521
Preliminary data
8.9.4 Conversion start modes
selected input channel. An interrupt, if enabled, will be generated after all selected
channels have been converted. The process will repeat starting with the first selected
channel. Additional conversion results will again cycle through the four result
registers, overwriting the previous results.Continous conversions continue until
terminated by the user.
Dual channel, continuous conversion mode:
continuous conversion mode where conversion occurs on two user-selectable inputs.
The result of the conversion of the first channel is placed in result register, AD1DAT0.
The result of the conversion of the second channel is placed in result register,
AD1DAT1. The first channel is again converted and its result stored in AD1DAT2. The
second channel is again converted and its result placed in AD1DAT3. An interrupt is
generated, if enabled, after every set of four conversions (two conversions per
channel).
Single step mode:
conversion mode. Any combination of the four input channels can be selected for
conversion. After each channel is converted, an interrupt is generated, if enabled,
and the A/D waits for the next start condition. May be used with any of the start
modes.
Timer triggered start:
a conversion has started, additional Timer 0 triggers are ignored until the conversion
has completed. The Timer triggered start mode is available in all A/D operating
modes.
Start immediately:
start mode is available in all A/D operating modes.
Edge triggered:
a conversion has started, additional edge triggers are ignored until the conversion
has completed. The edge triggered start mode is available in all A/D operating
modes.
An A/D conversion is started by rising or falling edge of P1.4. Once
Rev. 02 — 25 June 2004
8-bit microcontrollers with two-clock accelerated 80C51 core
This special mode allows ‘single-stepping’ in an auto scan
Programming this mode immediately starts a conversion.This
An A/D conversion is started by the overflow of Timer 0. Once
This is a variation of the auto scan
© Koninklijke Philips Electronics N.V. 2004. All rights reserved.
P89LPC904
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