45111 Datasheet, PDF (170/184 Pages) List of Unclassifed Manufacturers – 14-DAY MONEY BACK GUARANTEE

15 Appendix E: SX Data Sheet
15.3.2.8 CMP_B – Comparator Enable Register
CMP_B
76543210
EN OE Rsvd Rsvd Rsvd Rsvd Rsvd RES
EN -
OE -
Rsvd -
RES -
Comparator Enable, 0 = enabled, 1 = disabled
Comparator Output Enable, 0 = enabled, 1 = disabled
Reserved for future use
Comparator Result (EN must = 0)
15.3.3 Port C Registers
There are four registers used to configure the I/O pins of Port C. The TRIS_C register configures the
data direction of the Port C pins as input or output. The LVL_C register configures the input pins as
TTL or CMOS voltage level. The PLP_C register enables/disables pull up resistors on Port C input pins.
The ST_C register enables/disables the Schmitt-Trigger inputs on Port C input pins. To access these
registers you must first write a particular value to the MODE register. Please refer to Table 32 – SX20/28
Mode Register to find the values required in the MODE register to access the Port C Registers. Note: All
the bits in the following registers are set to ‘1’ on power up.
15.3.3.1 TRIS_C – Data Direction Register
TRIS_C
76543210
RC7 RC6 RC5 RC4 RC3 RC2 RC1 RC0
A bit set to ‘1’ in this register sets the corresponding I/O port pin to input (high z) mode.
A bit set to ‘0’ in this register sets the corresponding I/O port pin to output mode.
15.3.3.2 LVL_C - TTL/CMOS Select Register
LVL_C
76543210
RC7 RC6 RC5 RC4 RC3 RC2 RC1 RC0
A bit set to ‘1’ in this register sets the input level of the corresponding port pin to TTL.
A bit set to ‘0’ in this register sets the input level of the corresponding port pin to CMOS.
Page 170 • SX-Key/Blitz Development System Manual 2.0 • Parallax, Inc.