C509-L_97 SIEMENS [Siemens Semiconductor Group], C509-L_97 Datasheet - Page 82

• Manufacturer Part Number: C509-L_97
• Description: 8-Bit CMOS Microcontroller
• Manufacturer: SIEMENS [Siemens Semiconductor Group]

Special Function Register SYSCON (Address B1 H )
Special Function Register IP1 (Address B9 H )
Bit
PMOD
PDIR
Direction Registers DIR0-DIR6, DIR9 (Mapped Address = Port Address)
Bit
Bit 7...0
Semiconductor Group
Address. =
Port-Addr.
Bit No.
Bit No.
B1 H
B9 H
The shaded bits are not used for port selection.
Function
Port mode selection
PMOD = 0: Quasi-bidirectional port structure is selected (reset value)
PMOD = 1: Bidirectional port structure is selected.
Direction register enable
PDIR = 0:
PDIR = 1:
PDIR will automatically be cleared after the second machine cycle (S2P2) after
having been set.
Function
Port driver circuitry, input/output selection
Bit = 0:
Bit = 1:
This register can only be read and written by software when bit PDIR (IP1) was set
one instruction before.
MSB
CLKP PMOD
PDIR
MSB
.7
7
7
7
Port line is in output mode
Port line is in input mode (reset value).
.6
6
6
6
–
Port register access is enabled (reset value)
Direction register is enabled.
.5
5
.5
5
1
5
RMAP
.4
4
4
.4
4
6-4
.3
3
.3
3
–
3
On-Chip Peripheral Components
.2
2
.2
2
–
2
XMAP1 XMAP0
.1
1
.1
1
Reset Value : 1010XX01 B
1
Reset Value : 0X000000 B
LSB
LSB
.0
0
Reset Value : FF H
.0
0
0
Direction
Register
SYSCON
1997-10-01
IP1
C509-L