Timing

Notes on creating a device timing model

Fanout effect timing info. IIRC I saw about 20% variation across things

Wire

The following fields are consistent across node name (ie L/R doesn't effect):

• COST_CODE
• IS_INPUT_PIN
• IS_OUTPUT_PIN
• IS_PART_OF_BUS
• NUM_INTERSECTS
• NUM_TILE_PORTS
• SPEED_INDEX
• TILE_PATTERN_OFFSET

The following vary:

• ID_IN_TILE_TYPE
• IS_CONNECTED
• NUM_DOWNHILL_PIPS
• NUM_PIPS
• NUM_UPHILL_PIPS
• TILE_NAME

Node

The following fields are consistent across wire name (ie L/R doesn't effect):

• COST_CODE
• COST_CODE_NAME
• IS_BAD
• IS_COMPLETE
• IS_GND
• IS_VCC

The following vary:

• SPEED_CLASS
• IS_PIN
• IS_INPUT_PIN
• IS_OUTPUT_PIN
• PIN_WIRE
• NUM_WIRES

PIN_WIRE: sometimes 65535

SPEED_CLASS shifts around a lot depending on other parameter values, which also shift around. A few interesting comparisons

Sometimes it differs for no apparent reason. For example:

• BASE_CLOCK_REGION:X0Y3 CLASS:node COST_CODE:21 COST_CODE_NAME:HQUAD IS_BAD:0 IS_COMPLETE:1 IS_GND:0 IS_INPUT_PIN:0 IS_OUTPUT_PIN:0 IS_PIN:0 IS_VCC:0 NAME:INT_L_X0Y199/WW4BEG3 NUM_WIRES:13 PIN_WIRE:65535 SPEED_CLASS:100
• BASE_CLOCK_REGION:X0Y3 CLASS:node COST_CODE:21 COST_CODE_NAME:HQUAD IS_BAD:0 IS_COMPLETE:1 IS_GND:0 IS_INPUT_PIN:0 IS_OUTPUT_PIN:0 IS_PIN:0 IS_VCC:0 NAME:INT_L_X2Y199/WW4BEG3 NUM_WIRES:13 PIN_WIRE:65535 SPEED_CLASS:284

Pip

The following fields are consistent across node name (ie L/R doesn't effect):

• CAN_INVERT',
• IS_BUFFERED_2_0',
• IS_BUFFERED_2_1',
• IS_DIRECTIONAL',
• IS_EXCLUDED_PIP',
• IS_FIXED_INVERSION',
• IS_INVERTED',
• IS_PSEUDO',
• IS_SITE_PIP',
• IS_TEST_PIP',

The following vary:

• TILE