74377: Difference between revisions
From NESdev Wiki
Jump to navigationJump to search
m (remove pre, add section headings) |
m (bluh) |
||
Line 1: | Line 1: | ||
The | The [[74377]] chip (common variants 74LS377, 74HC377) is an octal D flip-flop, used as a latch in mappers like [[Color Dreams]] and stores eight bits of data. | ||
== 74377 Pinout == | == 74377 Pinout == | ||
.--\/--. | |||
/WE -| 1 | /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 | GND -|10 11|- CLK | ||
`------' | |||
== Signal descriptions == | == Signal descriptions == | ||
*Vcc: Connect to +5V | *Vcc: Connect to +5V |
Revision as of 04:27, 31 January 2013
The 74377 chip (common variants 74LS377, 74HC377) is an octal D flip-flop, used as a latch in mappers like Color Dreams and stores eight bits of data.
74377 Pinout
.--\/--. /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 `------'
Signal descriptions
- 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.
References
- Philips Semiconductors. 74HC377: Octal D-type flip-flop with data enable; positive-edge trigger