GMS90 Series
SPECIAL FUNCTION REGISTERS
All registers, except the program counter and the four general purpose register banks, reside in the special func-
tion register area.
The 28 special function registers (SFR) include pointers and registers that provide an interface between the CPU
and the other on-chip peripherals. There are also 128 directly addressable bits within the SFR area.
All SFRs are listed in Table 1, Table 1, and Table 3.
In Table 1 they are organized in numeric order of their addresses. In Table 2 they are organized in groups which
refer to the functional blocks of the GMS90 series. Table 3 illustrates the contents of the SFRs.
Table 1. Special Function Registers in Numeric Order of their Addresses
Contents after
Reset
Contentsafter
Reset
Address
Register
Address
Register
P0 1)
SP
DPL
P1 1)
80H
81H
82H
83H
84H
85H
86H
87H
FFH
07H
00H
00H
XXH 2)
XXH 2)
XXH 2)
90H
91H
92H
93H
94H
95H
96H
97H
FFH
00H
reserved
reserved
reserved
reserved
reserved
reserved
reserved
XXH 2)
XXH 2)
XXH 2)
XXH 2)
XXH 2)
XXH 2)
DPH
reserved
reserved
reserved
PCON
2)
0XX0000B
TCON 1)
TMOD
TL0
TL1
TH0
SCON 1)
SBUF
88H
89H
8AH
8BH
8CH
8DH
00H
00H
00H
00H
00H
00H
98H
99H
9AH
9BH
9CH
9DH
9EH
9FH
00H
XXH 2)
XXH 2)
XXH 2)
XXH 2)
XXH 2)
XXH 2)
XXH 2)
reserved
reserved
reserved
reserved
reserved
reserved
TH1
8EH 3)
8FH
☞
3)
3)
☞
reserved
XXH 2)
1) Bit-addressable Special Function Register.
2) X means that the value is indeterminate and the location is reserved.
3) The GMS9XX54/56/58 have the AUXR0 register at address 8E .
H
GMS9XX51/52
GMS9XX54/56/58
8EH
2)
2)
XXXXXXXXB
8EH
reserved
AUXR0
XXXXXXX0B
Dec. 1998 Ver 3.0
13
HYNIX [ HYNIX SEMICONDUCTOR ]
