File:Lawn-Tennis-Vertical-Sync.png: Difference between revisions

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(The vertical sync circuit is the same configuration as the horizontal sync system, except the drive pulse is the HRESET pulse, not the master clock or CLK. During counting after 256 counts this sets pin 5 (the 256V connection) of D9 high, then after another 1 + 4 = 261 counts to satisfy the inputs of the 7410 NAND gate D8, the output of D8 falls low. Then on the 262nd HRESET pulse the counters are reset. The division of the horizontal rate is therefore is 262. HRESET has a frequency of 15,7...)
 
m (attribution -> Dr. Hugo)
 
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The horizontal and vertical sync pulses are mixed together by the XOR
The horizontal and vertical sync pulses are mixed together by the XOR
gate A4 to become (not)composite sync.
gate A4 to become (not)composite sync.
Dr. Hugo R. Holden.
UPDATED Jan 2013.

Latest revision as of 23:39, 1 January 2024

Summary

The vertical sync circuit is the same configuration as the horizontal sync system, except the drive pulse is the HRESET pulse, not the master clock or CLK.

During counting after 256 counts this sets pin 5 (the 256V connection) of D9 high, then after another 1 + 4 = 261 counts to satisfy the inputs of the 7410 NAND gate D8, the output of D8 falls low. Then on the 262nd HRESET pulse the counters are reset.

The division of the horizontal rate is therefore is 262. HRESET has a frequency of 15,731 Hz, so VRESET has a frequency of 15731/262 = 60.04 Hz which is the Field frequency for the monitor or very close to it. The horizontal and vertical sync pulses are mixed together by the XOR gate A4 to become (not)composite sync.

Dr. Hugo R. Holden. UPDATED Jan 2013.

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current23:36, 1 January 2024Thumbnail for version as of 23:36, 1 January 20241,642 × 1,188 (996 KB)Wikiadmin (talk | contribs)The vertical sync circuit is the same configuration as the horizontal sync system, except the drive pulse is the HRESET pulse, not the master clock or CLK. During counting after 256 counts this sets pin 5 (the 256V connection) of D9 high, then after another 1 + 4 = 261 counts to satisfy the inputs of the 7410 NAND gate D8, the output of D8 falls low. Then on the 262nd HRESET pulse the counters are reset. The division of the horizontal rate is therefore is 262. HRESET has a frequency of 15,7...

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