Elements of STIL bridge design and test
Tony Taylor and Robert Ruiz, Synopsys, Mountain View, CA -- Test & Measurement World, 1/1/2001
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Figure 1 WGL Timeplate timeplate “_default_WFT_” period 100ns “CVBS” := input [0ps:S]; “CVBS” := output [0ps:X, 40ns:Q’edge]; “BLUE_TV” := input [0ps:S]; “BLUE_TV” := output [0ps:X, 40ns:Q’edge]; “GREEN_TV” := input [0ps:S]; “GREEN_TV” := output [0ps:X, 40ns:Q’edge]; “RED_TV” := input [0ps:S]; “RED_TV” := output [0ps:X, 40ns:Q’edge]; “BLUE” := input [0ps:S]; “BLUE” := output [0ps:X, 40ns:Q’edge]; “GREEN” := input [0ps:S]; “GREEN” := output [0ps:X, 40ns:Q’edge]; “RED” := input [0ps:S]; “RED” := output [0ps:X, 40ns:Q’edge]; “SCAN_ENABLE” := input [0ps:S]; << 32 similar lines deleted >> “CBE[3]” := output [0ps:X, 40ns:Q’edge]; “CBE[2]” := input [0ps:S]; “CBE[2]” := output [0ps:X, 40ns:Q’edge]; “CBE[1]” := input [0ps:S]; “CBE[1]” := output [0ps:X, 40ns:Q’edge]; “CBE[0]” := input [0ps:S]; “CBE[0]” := output [0ps:X, 40ns:Q’edge]; “AD[31]” := input [0ps:S]; “AD[31]” := output [0ps:X, 40ns:Q’edge]; << 497 similar lines deleted >> end STIL WaveformTable Timing { WaveformTable “_default_WFT_” { Period ‘100ns’; Waveforms { “_default_In_Timing_” { 0 { ‘0ns’ D; } } “_default_In_Timing_” { 1 { ‘0ns’ U; } } “_default_In_Timing_” { Z { ‘0ns’ Z; } } “_default_In_Timing_” { N { ‘0ns’ N; } } “_default_Clk0_Timing_” { P { ‘0ns’ D; ‘50ns’ U; ‘80ns’ D; } } “_default_Clk1_Timing_” { P { ‘0ns’ U; ‘50ns’ D; ‘80ns’ U; } } “_default_Out_Timing_” { X { ‘0ns’ X; } } “_default_Out_Timing_” { H { ‘0ns’ X; ‘40ns’ H; } } “_default_Out_Timing_” { T { ‘0ns’ X; ‘40ns’ T; } } “_default_Out_Timing_” { L { ‘0ns’ X; ‘40ns’ L; } } } } } |
| Figure 1 In the WGL Timeplate format (top), only one format for input and one format for output may be expressed. If multiple in or out formats are required, then multiple timeplates must be used. There is also a group format available in WGL, but the format above, expanded out by signal, is the way most tools require WGL data to be expressed. In the STIL WaveformTable (bottom), new waveform characters allow for multiple waveform flexibility. |
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Figure 2
STIL parallel vector for a
277-pin device: |
| Figure 2 Vector representation in STIL differs from that in WGL: In the WGL format depicted, each pin requires four characters: one for input, one for output, and a space following each. In another vector format, the in and out character may be postioned together, reducing the number of characters to three. Many readers, however, accept only the four-character format. The STIL representation uses a single-character representation that combines input and output characteristics. |
