Download Motorola MCP750 Technical data

Test Descriptions
DMA - Receive/Transmit DMA
Command Input
3
PPCx-Diag>SCC DMA
Description
This test will verify that the SCC can transmit and receive via internal
loopback, a 256-byte block of data that consists of all numbers between
0x00 and 0xFF.
The test will be performed under DMA control. A match of the contents of
the transmit and receive buffers will be verified. Due to the nature of
DMA, use of the ISA Bridge IC is also necessary.
Note
Because of the design of the Z85230, when DMA testing is
performed, data is still transmitted out of the device on the TxD
line. This may cause problems with terminals, modem, printers,
and any other device attached.
Response/Messages
After the command has been issued, the following line is printed:
SCC DMA: DMA Test....................... Running --->
If all parts of the test are completed correctly, then the test passes.
SCC DMA: DMA Test..................Running ---> PASSED
If all parts of the test are not completed correctly, then the test does not
pass. The receiver buffer may not be filled with the data before terminal
count. This results in either one or both controllers giving error messages:
SCC DMA: DMA Test..................Running ---> FAILED
SCC/DMA Test Failure Data:
(error message)
3-122
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