DRM050 — Rev 0
Designer Reference Manual
MOTOROLA
Receiver Firmware
39
Designer Reference Manual —
DRM050
Section 8. Receiver Firmware
8.1 Receiver Firmware Structure
The firmware consists of three main parts:
•
MAC Layer protocol
•
Application layer routines
•
USB interrupt routine
The MAC layer implements the RFWaves CSMA protocol. Please refer
to the section
4.1 MAC Layer Protocol
for a description of this layer.
Figure 8-1
shows the flow of the main application program. The USB
interrupt routine is not shown here. You may refer to another reference
design called
USB and PS2 Multimedia Keyboard by using the
MC68HC908JB8
for more detail
.
The main routine continually checks if there is any valid mouse or
keyboard data from the MAC layer. If so, the data will be converted to
USB report format and sent to the host via the endpoint 1 and endpoint 2.
IRQ serves for different interrupt events from the RFW-D100 chip when
USB is not in suspend mode.The IRQ ISR firmware will determine which
interrupt source caused the IRQ. It could be done by checking the IIR
register from RFW-D100 Baseband chip and then the corresponding
action can be taken by the interrupt service routine. During USB
suspend, the periodical wake-up trigger at IRQ can wake up MCU to
detect incoming packets and return to the host computer.
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Freescale Semiconductor, Inc.
For More Information On This Product,
Go to: www.freescale.com
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