45181 Parallax Inc, 45181 Datasheet - Page 174

• Manufacturer Part Number: 45181
• Description: SX TECH TOOL KIT NO POWER
• Manufacturer: Parallax Inc
• Series: SXr
• Type: Microcontrollerr

Specifications of 45181

• Contents: SX Book, SX Key, SX Tech Board, Samples, Resonators, Cable and Manual
• Product: Microcontroller Basic Stamps
• Operating Supply Voltage: 5 V
• For Use With/related Products: SX MCUs
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant

15 Appendix E: SX Data Sheet
15.4.3 Option
The OPTION register is a run-time writable register used to configure the RTCC and the Watchdog
Timer. The size of this register is affected by the OPTIONX device setting.
15.4.4 Fuse Registers
The Fuse registers are accessible only at program time. The SX-Key Development System Software
provides a convenient interface that is easy to use to customize the SX. You may use the predefined
Page 174 SX-Key/Blitz Development System Manual 2.0 Parallax, Inc.
When OPTION Extend = 0, bits 7 and 6 are implemented.
When OPTION Extend = 1, bits 7 and 6 read as ‘1’s.
RTW - If = 0, register $01 is W
RTI
RTS - If = 0, RTCC increments on internal instruction cycle
RTE - If = 0, RTCC increments on low-to-high transition
PSA - If = 0, prescaler is assigned to RTCC, divide rate determined by PS0-PS2 bits
- If = 0, RTCC roll-over interrupt is enabled
If = 1, register $01 is RTCC
If = 1, RTCC roll-over interrupt is disabled
If = 1, RTCC increments on transition of RTCC pin
If = 1, RTCC increments on high-to-low transition
If = 1, prescaler is assigned to WDT, and divide rate on RTCC is 1:1
PS2, PS1, PS0
RTW RTI RTS RTE PSA PS2 PS1 PS0
7
000
001
010
011
100
101
110
111
Figure 36 - Prescaler Division Ratios
6
5
Divide Rate
RTCC
OPTION
1:128
1:256
4
1:16
1:32
1:64
1:2
1:4
1:8
3
2
Watchdog Timer
Divide Rate
1
1:128
1:16
1:32
1:64
1:1
1:2
1:4
1:8
0