Service manual

UX-B20U/UX-B20C/B25C
5 – 13
µPD65945 (IC4) Pin descriptions
SYMBOL PIN NO. I/O DESCRIPTION PAD CELL. NOTE
SDRAM Bus Interface (33 pin)
RA0 35 O Address bus
L: Logic-0
H: Logic-1
FO09
RA1 34 O FO09
RA2 33 O FO09
RA3 32 O FO09
RA4 31 O FO09
RA5 30 O FO09
RA6 29 O FO09
RA7 28 O FO09
RA8 27 O FO09
RA9 26 O FO09
RA10 39 O FO09
RB 40 O Black select
L: Bank-0
H: Bank-1
FO09
RD0 9 I/O Data bus
L: Logic-0
H: Logic-1
B00U
RD1 8 I/O B00U
RD2 7 I/O B00U
RD3 6 I/O B00U
RD4 5 I/O B00U
RD5 4 I/O B00U
RD6 3 I/O B00U
RD7 2 I/O B00U
RD8 19 I/O B00U
RD9 18 I/O B00U
RD10 17 I/O B00U
RD11 16 I/O B00U
RD12 15 I/O B00U
RD13 14 I/O B00U
RD14 13 I/O B00U
RD15 12 I/O B00U
RCS_N 41 O Chip select
L: Select
H: Deselect
FO09
RRAS_N 42 O Command/Control
L: Active
H: In Active
FO09
RCAS_N 43 O FO09
RWE_N 44 O FO09
PCLK 22 O SDRAM operation clock FE04 32.256 MHz