MCP2120 datasheet(40/64 Pages) MICROCHIP

40 / 64 page

MCP2120/MCP2150 USER’S GUIDE

DS51246A-page 36

 2001 Microchip Technology Inc.

3.6.1.

System Debug Tips

If you are not getting communications between the two boards, some

debugging is in order. Here are some suggested steps:

• Verify that the Hyperterminal programs are set up correctly

• Verify that both Hyperterminal sessions are “connected”

• Verify that the MCP2120 Developer’s Boards are powered

• Verify that the MCP2120 Developer’s Boards are set up correctly

If that review does not locate the issue, then more in depth debugging is

required. These steps require an oscilloscope. A digital 4-channel

oscilloscope is recommended. By typing a data byte into Hyperterminal on the

PC, the oscilloscope can be used to determine where in the system the data

byte was “lost”.

Figure 3.19 and Figure 3.20 shows a debug flow to help troubleshoot the

communications between the two MCP2120 Developer’s Boards. Figure 3.19

shows the steps for the transmit side of System #1 (PC #1 and MCP2120

Developer’s Board #1). If it appears that the TXIR signal is correct, then the

receive side needs to be validated. Figure 3.20 shows the steps for the

receive side of System #2 (PC #2 and MCP2120 Developer’s Board #2).

These steps can then be used to debug the transmit side of System #2 and

the receive side of System #1.

MCP2120 데이터시트(PDF) 40 Page - Microchip Technology