GMS90C320 Datasheet, PDF (13/46 Pages) Hynix Semiconductor – HYNIX SEMICONDUCTOR INC. 8-BIT SINGLE-CHIP MICROCONTROLLERS

GMS90C320
CPU
The GMS90C320 is efficient both as a controller and as an arithmetic processor. It has extensive facilities for binary and BCD
arithmetic and excels in its bit-handling capabilities. Efficient use of program memory results from an instruction set con-
sisting of 44% one-byte, 41% two-byte, and 15% three-byte instructions. With a 12 MHz crystal, 58% of the instructions are
executed in 1.0µs.
Special Function Register PSW
MSB
Bit No.
7
6
Addr. D0_H
CY
AC
5
4
3
2
F0 RS1 RS2 OV
LSB
1
0
F1
P PSW
Bit
Function
CY
Carry Flag
AC
Auxiliary Carry Flag (for BCD operation)
F0
General Purpose Flag
RS1
RS0
Register Bank select control bits
0
0
Bank 0 selected, data address 00_H-07_H
0
1
Bank 1 selected, data address 08_H-0F_H
1
0
Bank 2 selected, data address 10_H-17_H
1
1
Bank 3 selected, data address 18_H-1F_H
OV
Overflow Flag
F1
General Purpose Flag
P
Parity Flag
Set/cleared by hardware each instruction cycle to indicate an odd/
even number of “one” bits in the accumulator, i.e. even parity.
Reset value of PSW is 00_H.
OCT. 2000 Ver 1.2
9