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scan_module [2019/01/21 11:26]
gary
scan_module [2019/01/21 11:27] (current)
gary
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 The encoder sync pulse is obtained directly from the encoder counting chip inside the controller. ​ This encoder chip can be loaded with a “compare” position, so that whenever the current encoder count is equal to the “compare” count, a flag pin on the chip becomes active. ​ We add additional circuitry to latch the sync pulse during the active part of the scan. The encoder sync pulse is obtained directly from the encoder counting chip inside the controller. ​ This encoder chip can be loaded with a “compare” position, so that whenever the current encoder count is equal to the “compare” count, a flag pin on the chip becomes active. ​ We add additional circuitry to latch the sync pulse during the active part of the scan.
  
-Pulses for the pixel clock are derived from a processed signal coming from the controller’s microprocessor (DIVIDE-by-N) on the normal TTL_OUT BNC.  The pulses from the encoder are sent to an interrupt line on the controller’s microprocessor. ​ The interrupt causes a programmable counter to count down.  When the counter reaches zero, the microprocessor sends a pulse to the TTL_OUT connector. ​ These pulses are only enabled during the active scan line.+Pulses for the pixel clock are derived from a processed signal coming from the controller’s microprocessor (DIVIDE-by-N) on the normal TTL_OUT BNC connector.  The pulses from the encoder are sent to an interrupt line on the controller’s microprocessor. ​ The interrupt causes a programmable counter to count down.  When the counter reaches zero, the microprocessor sends a pulse to the TTL_OUT connector. ​ These pulses are only enabled during the active scan line.
  
 [{{ scan_capture.png?​direct&​300 |Figure 1: Timing Example}}] [{{ scan_capture.png?​direct&​300 |Figure 1: Timing Example}}]
scan_module.txt · Last modified: 2019/01/21 11:27 by gary