Pen ADC (PADC) Operation
MOTOROLA
Analog Signal Processor (ASP)
15-5
As a result, the input range can be adjusted to fit different panels by tuning the resister value.
NOTE:
The voltage level at all input pins, including XY and U channel, must not
exceed QVDD—that is, 1.8 V.
15.4.2 Sample Rate Control
Table 15-4 shows the maximum PADC sample rates.
Figure 15-3. Pen Input Sampling Timing
Figure 15-3 shows the sample timing when AUTO = 1, AZE = 1 and MOD [1:0] = 10.
The output data rate can be calculated using the equations shown in Table 15-5. The variables used in the
equations are fields of the Pen A/D Sample Rate Control Register (ASP_PSMPLRG).
•
DSCNT (t1)—Data setup count: This controls the time for the MUX and touch panel to settle. The
max value is 1.575ms at ACLK = 12MHz.
•
DMCNT (t2)—Decimation count: This controls the number of samples to be averaged, which
effectively performs a simple comb filter as the second-stage decimation filter.
Table 15-4. Pen ADC Maximum Sample Rate
MODE (Auto)
DMCNT
IDLECNT
DSCNT
Maximum
Sample Rate
ZXY
0
0
1
1.5 kHz
ZXYU
0
0
1
1.1 kHz
U
0
0
0
9.6 kHz
t1
t2
t3
idle
idle
idle
data Z
into
FIFO
data X
into
FIFO
data Y
into
FIFO
data U
into
FIFO
data Z
into
FIFO
data X
into
FIFO
data Y
into
FIFO
data U
into
FIFO
t1 = Transistor switching and input selecting set up time, controlled by DSCNT
t2 = Data setup time, controlled by DSCNT and DMCNT
t3 = Point to point capture idle time, controlled by IDLECNT
Summary of Contents for DragonBall MC9328MX1
Page 68: ...1 12 MC9328MX1 Reference Manual MOTOROLA Introduction ...
Page 86: ...2 18 MC9328MX1 Reference Manual MOTOROLA Signal Descriptions and Pin Assignments ...
Page 116: ...3 30 MC9328MX1 Reference Manual MOTOROLA Memory Map ...
Page 126: ...4 10 MC9328MX1 Reference Manual MOTOROLA ARM920T Processor ...
Page 160: ...8 8 MC9328MX1 Reference Manual MOTOROLA System Control ...
Page 272: ...13 32 MC9328MX1 Reference Manual MOTOROLA DMA Controller ...
Page 281: ...Programming Model MOTOROLA Watchdog Timer Module 14 9 ...
Page 282: ...14 10 MC9328MX1 Reference Manual MOTOROLA Watchdog Timer Module ...
Page 300: ...15 18 MC9328MX1 Reference Manual MOTOROLA Analog Signal Processor ASP ...
Page 438: ...18 16 MC9328MX1 Reference Manual MOTOROLA Serial Peripheral Interface Modules SPI 1 and SPI 2 ...
Page 478: ...19 40 MC9328MX1 Reference Manual MOTOROLA LCD Controller ...
Page 574: ...21 32 MC9328MX1 Reference Manual MOTOROLA Memory Stick Host Controller MSHC Module ...
Page 598: ...23 16 MC9328MX1 Reference Manual MOTOROLA Real Time Clock RTC ...
Page 670: ...24 72 MC9328MX1 Reference Manual MOTOROLA SDRAM Memory Controller ...
Page 726: ...25 56 MC9328MX1 Reference Manual MOTOROLA SmartCard Interface Module SIM ...
Page 736: ...26 10 MC9328MX1 Reference Manual MOTOROLA General Purpose Timers ...
Page 854: ...29 18 MC9328MX1 Reference Manual MOTOROLA I2C Module ...
Page 900: ...30 46 MC9328MX1 Reference Manual MOTOROLA Synchronous Serial Interface SSI ...
Page 942: ...32 26 MC9328MX1 Reference Manual MOTOROLA GPIO Module and I O Multiplexer IOMUX ...