Samsung S3C84E5 user manual Converter Control Register Adcon, 15-2

A/D CONVERTER S3C84E5/C84E9/P84E9

A/D CONVERTER CONTROL REGISTER (ADCON)

The A/D converter control register, ADCON, is located in set1, bank 0 at address F7H. ADCON is read-write addressable using 8-bit instructions only. But, the EOC bit, ADCON.3 is read only. ADCON has four functions:

—Bits 6–4 select an analog input pin (ADC0–ADC7).

—Bit 3 indicates the end of conversion status of the A/D conversion.

—Bits 2–1 select a conversion speed.

—Bit 0 starts the A/D conversion.

Only one analog input channel can be selected at a time. You can dynamically select any one of the eight analog input pins, ADC0–ADC7 by manipulating the 3-bit value for ADCON.6–ADCON.4

A/D Converter Control Register (ADCON)

F7H, Set 1, Bank 0, R/W (ADCON.3 bit is read-only)

MSB

.7

.6

.5

.4

.3

.2

.1

.0

LSB

Not used							Start or Enable bit
(must keep always 0)							0 = Disable Operation
							1 = Start Operation
	A/D Input Pin Selection bits:
				Clock Selection bit:
.6.5.4		A/D Input pin
				.2		.1	Conversion Clock
000		ADC0
001		ADC1		0		0	fxx/16
010		ADC2		0		1	fxx/8
011		ADC3		1		0	fxx/4
100		ADC4		1		1	fxx
101		ADC5
110		ADC6	End-of-Conversion bit (realy only):
111		ADC7
			0 = Conversion not complete
			1 = Conversion complete

Figure 15-1. A/D Converter Control Register (ADCON)

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