AN2818 Freescale Semiconductor / Motorola, AN2818 Datasheet - Page 19

• Manufacturer Part Number: AN2818
• Description: Romeo2 Monitor for the MC68HC908AP64 MCU
• Manufacturer: Freescale Semiconductor / Motorola

Romeo2 Monitor Source Code
5. Set reset pin to logic 1 using command RESET 1 <return>.
Figure 11. Receiving Data Without Manchester Encoding
Romeo2 Monitor Source Code
The Romeo2 monitor was written using the C programming language. Full source code is supplied in file
Romeo2AP64MonSource.zip, which can be downloaded from www.freescale.com.
Modifying Romeo2 Monitor
The Romeo monitor program has a simple structure. It has been written to allow easy porting to other
MCUs. The code is liberally commented and should be easy to understand.
Decoding of commands typed into the PC terminal program is done in the SCIRx() routine. This routine
is called each time the MCU receives a character from the PC keyboard. It stores characters in a buffer
until a carriage return is detected. It then decodes the buffer and performs the required function for each
message.
When configuring the internal registers on Romeo2, the monitor uses the MCU's SPI peripheral. It also
uses the SPI when the RECEIVE command is used to receive data from Romeo2.
The monitor uses the following MCU resources.
Romeo2 Monitor for the MC68HC908AP64 MCU, Rev. 0
Freescale Semiconductor
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