External Signal Description - Freescale Semiconductor MCF52277 Reference Manual

22.2

External Signal Description

ASP external signal names are listed in the following table.
Signal Name I/O
ADC_REF I External ADC reference voltage
ADC_IN[7:0] I Touchscreen and/or ADC inputs. ADC_IN[7:0] serves as a touchscreen interface or generic ADC
interface, determined by ASP_CR[TSE]. Also, the touchscreen signal functionality for these pins
depends on the setting of ASP_CR[TSTYPE]. The available configurations are shown in the table
below.
22.3 Memory Map/Register Definition
The ASP module registers are summarized in
Address
0xFC0A_8000 ASP Control Register (ASP_CR)
0xFC0A_8004 ASP Sampling Setting Register (ASP_SET)
0xFC0A_8008 A/D Sampling Timing Register (ASP_TIM)
0xFC0A_800C ASP Interrupt/DMA Control Register (ASP_ICR)
Freescale Semiconductor
Table 22-1. ASP Signal Descriptions
ADC_IN[7:0]
1
ADC_IN7 —
1
ADC_IN6 —
1
ADC_IN5 —
1
—
ADC_IN4
ADC_IN3 LR/Y–
ADC_IN2 LL/Y+
ADC_IN1 UR/X–
ADC_IN0 UL/X+
1
May be used as a general-purpose ADC signal by setting the
appropriate ASP_CR[APTN] bit.
Note: LR: lower-left, LL: lower-left, UR: upper-right, UL: upper-left
Table 22-2.
Table 22-2. ASP Memory Map
Register
MCF52277 Reference Manual, Rev. 1
Touchscreen Controller/Analog-to-Digital Converter
Description
Touchscreen
(TSE = 1)
1 1
— — X−
force
1
— LR X+
sense force
1
— UL Y−
sense sense
Wiper/ Wiper Y+
sense
Sense
LR Y− Y−
force
LL Y+ Y+
force
UR X− X−
sense
UL X+ X+
sense
Width
Access Reset Value Section/Page
(bits)
32 R/W
32 R/W
32 R/W
32 R/W
ADC
(TSE = 0)
ADC_IN7
ADC_IN6
ADC_IN5
ADC_IN4
ADC_IN3
ADC_IN2
ADC_IN1
ADC_IN0
0x0008_0000 22.3.1/22-4
0x7787_0000 22.3.2/22-7
0x000F_0FFF 22.3.3/22-8
0x0020_0000 22.3.4/22-9
22-3