Lexmark C750 Service Manual - Page 205

5060-00x ROM Test The ROM Test is used to check the validity of the controller board code and fonts. To run the ROM Test: 1. Select ROM Test from the menu. P and F represent the same numbers for DRAM. The power indicator blinks indicating the test is in progress. The test runs continuously. 2. Press Return or Stop to exit the test. Each time the test finishes, the screen updates with the result. If the test passes, the Pass Count increases by 1, however if the test fails, one of the following messages appears for approximately three seconds: ROM Checksum Error ROM Burst Read Error Once the maximum pass count or fail count is reached, the test stops with the power indicator on solid. The final results are displayed. Parallel Wrap Test Use this test with a wrap plug to check operation of the parallel port hardware. Each parallel signal is tested. To run the Parallel Wrap Test: 1. Disconnect the parallel interface cable and install the wrap plug (P/N 1319128). 2. Select Parallel Wrap Test from the menu. The power indicator blinks indicating the test is in progress. The test runs continuously until canceled. Each time the test finishes, the screen updates. If the test passes, the Pass Count increases by 1, however if the test fails, one of the following messages appears for approximately three seconds: Sync Busy Error Byte Interrupt Request Error Strobe Interrupt Request Error Init Fail Error Init Busy Error Init Rise Error Host Busy Error RAM Data FF Error RAM Data AA Error RAM Data 00 Error RAM Data 55 Error DMA Count Error DMA Address Error DMA Interrupt Error DMA Memory Error DMA Background Error Clear Init Rise Error False Init Rise Error Autofeed Rising Interrupt Error Clear Autofeed Rise Error False Autofeed Rise Error Autofeed Falling Interrupt Error Clear Autofeed Fall Error 3. Once the maximum count is reached the test stops. The power indicator goes on solid and the final results are displayed. Press Return or Stop to exit the test. Diagnostic aids 3-21