IV ANALOG BLOCK: A/D CONVERTER
B-IV-2-2
EPSON
S1C33T01 FUNCTION PART
I/O Pins of A/D Converter
Table 2.1 shows the pins used by the A/D converter.
Table 2.1
I/O Pins of A/D Converter
Pin name
I/O
Function
Function select bit
K52/#ADTRG
I
Input port / AD trigger
CFK52(D2)/K5 function select register(0x402C0)
K60/AD0
I
Input port / AD converter input 0
CFK60(D0)/K6 function select register(0x402C3)
K61/AD1
I
Input port / AD converter input 1
CFK61(D1)/K6 function select register(0x402C3)
K62/AD2
I
Input port / AD converter input 2
CFK62(D2)/K6 function select register(0x402C3)
K63/AD3
I
Input port / AD converter input 3
CFK63(D3)/K6 function select register(0x402C3)
K64/AD4
I
Input port / AD converter input 4
CFK64(D4)/K6 function select register(0x402C3)
K65/AD5
I
Input port / AD converter input 5
CFK65(D5)/K6 function select register(0x402C3)
K66/AD6
I
Input port / AD converter input 6
CFK66(D6)/K6 function select register(0x402C3)
K67/AD7
I
Input port / AD converter input 7
CFK67(D7)/K6 function select register(0x402C3)
AVDDE
–
Power supply for analog system (+)
–
AVDDE (analog power-supply pin)
AVDDE is the power-supply pin for the analog circuit. The voltage level supplied to this pin must be AVDDE =
VDDE.
Note: If the A/D converter is enabled, even when the A/D converter is not operated current will flow
between AVDDE and VSS and result in power consumption. Therefore, applications should disable
the A/D converter when it is not being used by setting ADE (D2) in the A/D enable register
(0x40244) to "0" (the default value).
AD[7:0] (analog-signal input pins)
The analog input pins AD7 (Ch.7) through AD0 (Ch.0) are shared with input port pins K67 through K60.
Therefore, when these pins are used for analog input, they must be set for use with the A/D converter in the
software. This setting can be made individually for each pin. At cold start, all these pins are set for input ports.
The analog input voltage AVIN can be input in the range of VSS
≤ AVIN ≤ AVDDE.
#ADTRG (external-trigger input pin)
This pin is used to input a trigger signal to start A/D conversion from an external source. Since this pin is shared
with input port K52, it must be set for use with the A/D converter in the software before an external trigger can
be applied to the pin. At cold start, this pin is set for an input port.
Method for setting A/D-converter input pins
At cold start, the #ADTRG and AD[7:0] pins all are set for input ports Kxx (function select bit CFKxx = "0").
When using these pins for the A/D converter, write "1" to the function select bit CFKxx.
At hot start, these pins retain their state from prior to the reset.