74377: Difference between revisions

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(Felt this page needed to exist. The Color Dreams mapper page links to it anyway)
 
(Added pinout)
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The 74377 chip is used as a latch in mappers like [[Color Dreams]] and stores eight bits of data
The 74377 chip is used as a latch in mappers like [[Color Dreams]] and stores eight bits of data.
<pre>
      74HC377
  Octal D flip-flop
    ,---_---.
/WE -| 1  20|- Vcc
Q0 -| 2  19|- Q7
D0 -| 3  18|- D7
D1 -| 4  17|- D6
Q1 -| 5  16|- Q6
Q2 -| 6  15|- Q5
D2 -| 7  14|- D5
D3 -| 8  13|- D4
Q3 -| 9  12|- Q4
GND -|10  11|- CLK
    `-------'
</pre>
*Vcc: Connect to +5V
*GND:
*CLK: Load clock
*/WE: Write enable
*D0-7: Inputs, connected to CPU D0-D7
*Q0-7: Outputs, connected to PRG and CHR ROM address lines
D0-7 are copied to Q0-7 when CLK rises (0 to 1) while /WE is low.

Revision as of 16:11, 27 November 2010

The 74377 chip is used as a latch in mappers like Color Dreams and stores eight bits of data.

      74HC377
  Octal D flip-flop
     ,---_---.
/WE -| 1   20|- Vcc
 Q0 -| 2   19|- Q7
 D0 -| 3   18|- D7
 D1 -| 4   17|- D6
 Q1 -| 5   16|- Q6
 Q2 -| 6   15|- Q5
 D2 -| 7   14|- D5
 D3 -| 8   13|- D4
 Q3 -| 9   12|- Q4
GND -|10   11|- CLK
     `-------'
  • Vcc: Connect to +5V
  • GND:
  • CLK: Load clock
  • /WE: Write enable
  • D0-7: Inputs, connected to CPU D0-D7
  • Q0-7: Outputs, connected to PRG and CHR ROM address lines

D0-7 are copied to Q0-7 when CLK rises (0 to 1) while /WE is low.