SX18AC/SO Parallax Inc, SX18AC/SO Datasheet - Page 11

• Manufacturer Part Number: SX18AC/SO
• Description: IC MCU 2K FLASH 50MHZ SO-18
• Manufacturer: Parallax Inc
• Series: SXr

Specifications of SX18AC/SO

• Core Processor: RISC
• Core Size: 8-Bit
• Speed: 50MHz
• Number Of I /o: 12
• Program Memory Size: 3KB (2K x 12)
• Program Memory Type: FLASH
• Ram Size: 137 x 8
• Oscillator Type: Internal
• Operating Temperature: 0°C ~ 70°C
• Package / Case: 18-SOIC
• Voltage - Supply (vcc/vdd): -
• Eeprom Size: -
• Data Converters: -
• Peripherals: -
• Connectivity: -

4.3 OPTION Register
When the OPTIONX bit in the FUSE word is cleared, bits
7 and 6 of the OPTION register are implemented.
When the OPTIONX bit is set, bits 7 and 6 of the
OPTION register read as ‘1’s.
© 1998 Scenix Semiconductor, Inc. All rights reserved.
RTW
RTE_IE
RTS
RTE_ES
PSA
PS2-PS0
RTW RTE
Bit 7
_IE
RTCC/W register selection:
0 = Register 01h addresses W
1 = Register 01h addresses RTCC
RTCC edge interrupt enable:
0 = RTCC roll-over interrupt is enabled
1 = RTCC roll-over interrupt is disabled
RTCC increment select:
0 = RTCC increments on internal instruction
cycle
1 = RTCC increments upon transition on
RTCC pin
RTCC edge select:
0 = RTCC increments on low-to-high transi-
tions
1 = RTCC increments on high-to-low transi-
tions
Prescaler Assignment:
0 = Prescaler is assigned to RTCC, with di-
vide rate determined by PS0-PS2 bits
1 = Prescaler is assigned to WDT, and divide
rate on RTCC is 1:1
Prescaler divider (see Table 4-2)
RTS
RTE
_ES
PSA
PS2
PS1
Bit 0
PS0
- 11 -
Upon reset, all bits in the OPTION register are set to 1.
PS2, PS1, PS0
000
001
010
011
100
101
110
111
Table 4-2. Prescaler Divider Ratios
Divide Rate
RTCC
1:2
1:4
1:8
1:16
1:32
1:64
1:128
1:256
SX18AC / SX20AC / SX28AC
Watchdog Timer
Divide Rate
1:1
1:2
1:4
1:8
1:16
1:32
1:64
1:128
www.scenix.com