AR1100 Datasheet, PDF (33/58 Pages) Microchip Technology – AR1100 Resistive USB and RS-232 Touch Screen Controller

AR1100 RESISTIVE USB AND RS-232 TOUCH SCREEN CONTROLLER
8.0 BOOT LOADER
The boot load process and associated commands
enables the host to reprogram the AR1100. Because
the size of the Flash program memory cannot accom-
modate both a boot load section and application sec-
tion, the AR1100 is programmed in sections using 3
passes. With each pass, a USB device will necessarily
re-enumerate.
Note:
The boot load operation is supported only
in UART and HID-GENERIC
communication modes. Refer to
Section 7.6, USB Mode Change.
FIGURE 8-1:
BOOT LOADING SEQUENCE
Note:
A stand-alone software utility is available
from Microchip to facilitate the boot
loading operation. This functionality is
also available with the Microchip AR
Configuration Utility.
Passes:
1. Program temporary boot load application into
upper memory
2. Execute from temporary boot load application to
program the lower half of the new application
3. Execute from the lower half of the new applica-
tion to program the upper half
This process is illustrated in a more detail in Figure 8-1
below.
 2011 Microchip Technology Inc.
DS41606B-page 33