AR1100-I MICROCHIP [Microchip Technology], AR1100-I Datasheet - Page 30

• Manufacturer Part Number: AR1100-I
• Description: AR1100 Resistive USB and RS-232 Touch Screen Controller
• Manufacturer: MICROCHIP [Microchip Technology]

7.2.3
The host first commands the AR1100 to enter
Calibration mode, then subsequently presents the
calibration point targets, one at a time, from left to right,
top to bottom. The AR1100 returns a calibration
command response packet each time the operator
touches a target – signaling the host to proceed. Upon
completion, the data from the calibration process is
saved to EEPROM and available for use by the
AR1100 during normal operation. Calibration process
can be aborted by the host by simply issuing any
command. That command will be ignored but the
response to that command will have a status byte that
indicates that calibration had terminated prematurely
(see below).
7.2.3.1
• host issues calibration command: <0x55>
• host present 1
• operator touches (and releases) sensor at 1
• device issues response packet: <0x55> <0x02>
• host presents 2
• operator touches (and releases) sensor at 2
• device issues response packet: <0x55> <0x02>
• …
• host presents last target
• operator touches (and releases) sensor at last
• device issues response packet: <0x55> <0x02>
• host terminates the target display
• device returns to normal operation
7.2.3.2
• host issues calibration command: <0x55>
• host presents 1
• operator touches (and releases) sensor at 1
• device issues response packet: <0x55> <0x02>
DS41606B-page 30
<0x02> <0x14> <type>
target
<0x00> <0x14>
target
<0x00> <0x14>
target
<0x00> <0x14>
<0x02> <0x14> <type>
target
<0x00> <0x14>
EXECUTION
Normal sequence
Aborted sequence
st
nd
st
target
target
target
st
nd
st
• host presents 2
• operator touches (and releases) sensor at 2
• device issues response packet: <0x55> <0x02>
• host issues TOUCH_ENABLE command to abort
• device issues response packet: <0x55> <0x02>
• (status 0xFC indicates calibration termination)
• host terminates the target display
• device returns to normal operation
7.2.3.3
The VCF (Verbose Calibration Feedback) bit in the
TouchOptions Configuration register enables ‘verbose’
communication from the AR1100 in Calibration mode
as evidenced below:
• host sets ‘verbose’ flag in Configuration register
• host issues calibration command: <0x55>
• device responds: <0x55> <0x07> <0x00>
0xFE indicates ‘enter’ Calibration mode, XX and YY are
don’t care.
• host presents 1
• operator touches (and releases) sensor at 1
• device issues response packet: <0x55> <0x07>
• the 5
0xXXXX and 0xYYYY are RAW coordinates of the
touch point (16-bit, little endian)
• host presents 2
• operator touches (and releases) sensor at 2
• device issues response packet: <0x55> <0x07>
• The 5
0xXXXX and 0xYYYY are RAW coordinates of the
touch point (16-bit, little endian)
target
<0x00> <0x14>
calibration: <0x55> <0x01> <0x12>
<0xFC> <0x12>
i.e., TouchOptions[VCF]
<0x02> <0x14> <type>
<0x14> <0xFE> <0xXX> <0xXX> <0xYY>
<0xYY>
target
<0x00> <0x14> <0x00> <0xXX> <0xXX>
<0xYY> <0xYY>
(the 1
target
<0x00> <0x14> <0x01> <0xXX> <0xXX>
<0xYY> <0xYY>
(the 2
th
st
th
nd
…
byte indicates the calibration point 0x00
)
)
byte indicates the calibration point 0x01
Normal sequence (verbose)
nd
st
nd
target
target
target
 2011 Microchip Technology Inc.
nd
st
nd