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Genesis Microchip Confidential ***
gm5110/20 Preliminary Data Sheet
June 2002
34
C5110-DAT-01C
4.14.2 Full-Custom Configuration
In full-custom configuration the OCM executes a firmware program running from external
ROM. This is illustrated in Figure 23B. A parallel port with separate address and data busses
is available for this purpose. This port connects directly to standard, commercially available
ROM or programmable Flash ROM devices. Normally 64KB or 128KB of ROM is required.
Both instructions and data are fetched from external ROM on a cycle-by-cycle basis. The
speed of the accesses on the parallel port is determined by the gm5110/20 internal
OCM_CLK. This in turn determines the speed of the external ROM device. For example, if a
14.3 MHz crystal is being used to produce TCLK, and the OCM_CLK is derived from
TCLK, then a 45ns ROM can be used.
To program gm5110/20 in full-custom configuration the content of the external ROM is
generated using Genesis software development tools G-Wizard and OSD-Workbench. This is
illustrated in Figure 25. G-Wizard is a GUI-based tool for capturing system information such
as panel timing, support modes, system configuration, etc. OSD-Workbench is a GUI based
tool for defining OSD menus and functionality.
ROM Programmer
External ROM
Image File (.hex)
Firmware source files (*.c *.h)
G-Wizard
gm5110/20 Driver
OSD Workbench
gm5110/20 Driver
OCM
ROM
Keil Compiler
gm5110/20
LCD
Controller
Board
Figure 25.
Programming the OCM in Full-Custom Configuration