458 B
458 B
6309 Board Prototype #1 Specs
HD63C09 CPU @ 3MHz HM62256BLP-7 SRAM AT28C256-15 EEPROM ST16C550 UART @ 1.8342MHz (XO due to lack of 22pf 1.8432MHz XTALs)
Memory Map
Device | Location |
---|---|
EEPROM | 8000-FFFF |
UART | 7F00-7FFF |
SRAM | 0000-7EFF |
Truth Table
A15 | A14-A9 | A8 | Chip |
---|---|---|---|
H | x | x | EEPROM |
L | x | L | SRAM |
L | H | H | UART |