Datasheet
Table Of Contents
- List of Sections
- Table of Contents
- List of Figures
- List of Tables
- Section 1. General Description
- 1.1 Contents
- 1.2 Introduction
- 1.3 Features
- 1.4 MCU Block Diagram
- 1.5 Pin Assignments
- 1.6 Pin Functions
- 1.6.1 Power Supply Pins (Vdd and Vss)
- 1.6.2 Oscillator Pins (OSC1 and OSC2)
- 1.6.3 External Reset Pin (RST)
- 1.6.4 External Interrupt Pin (IRQ)
- 1.6.5 Analog Power Supply Pin (VDDA)
- 1.6.6 Analog Ground Pin (VSSA)
- 1.6.7 Analog Ground Pin (AVSS/VREFL)
- 1.6.8 ADC Voltage Reference Pin (VREFH)
- 1.6.9 Analog Supply Pin (VDDAREF)
- 1.6.10 External Filter Capacitor Pin (CGMXFC)
- 1.6.11 Port A Input/Output (I/O) Pins (PTA7-PTA0)
- 1.6.12 Port B I/O Pins (PTB7/ATD7-PTB0/ATD0)
- 1.6.13 Port C I/O Pins (PTC5-PTC0)
- 1.6.14 Port D I/O Pins (PTD7-PTD0)
- 1.6.15 Port E I/O Pins (PTE7/SPSCK-PTE0/TxD)
- 1.6.16 Port F I/O Pins (PTF7-PTF0/TACH2)
- 1.6.17 Port G I/O Pins (PTG2/KBD2-PTG0/KBD0)
- 1.6.18 Port H I/O Pins (PTH1/KBD4-PTH0/KBD3)
- 1.7 I/O Pin Summary
- 1.8 Signal Name Conventions
- 1.9 Clock Source Summary
- Section 2. Memory Map
- Section 3. Random-Access Memory (RAM)
- Section 4. FLASH Memory
- Section 5. EEPROM
- Section 6. Configuration Register (CONFIG)
- Section 7. Central Processor Unit (CPU)
- Section 8. System Integration Module (SIM)
- Section 9. Clock Generator Module (CGM)
- 9.1 Contents
- 9.2 Introduction
- 9.3 Features
- 9.4 Functional Description
- 9.5 I/O Signals
- 9.5.1 Crystal Amplifier Input Pin (OSC1)
- 9.5.2 Crystal Amplifier Output Pin (OSC2)
- 9.5.3 External Filter Capacitor Pin (CGMXFC)
- 9.5.4 PLL Analog Power Pin (VDDA)
- 9.5.5 Oscillator Enable Signal (SIMOSCEN)
- 9.5.6 Crystal Output Frequency Signal (CGMXCLK)
- 9.5.7 CGM Base Clock Output (CGMOUT)
- 9.5.8 CGM CPU Interrupt (CGMINT)
- 9.6 CGM Registers
- 9.7 Interrupts
- 9.8 Low-Power Modes
- 9.9 CGM During Break Interrupts
- 9.10 Acquisition/Lock Time Specifications
- Section 10. Monitor ROM (MON)
- Section 11. Timer Interface Module A (TIMA)
- Section 12. Timer Interface Module B (TIMB)
- Section 13. Programmable Interrupt Timer (PIT)
- Section 14. Analog-to-Digital Converter (ADC)
- Section 15. Serial Communications Interface Module (SCI)
- Section 16. Serial Peripheral Interface Module (SPI)
- 16.1 Contents
- 16.2 Introduction
- 16.3 Features
- 16.4 Pin Name Conventions and I/O Register Addresses
- 16.5 Functional Description
- 16.6 Transmission Formats
- 16.7 Queuing Transmission Data
- 16.8 Error Conditions
- 16.9 Interrupts
- 16.10 Resetting the SPI
- 16.11 Low-Power Modes
- 16.12 SPI During Break Interrupts
- 16.13 I/O Signals
- 16.14 I/O Registers
- Section 17. Input/Output (I/O) Ports
- Section 18. External Interrupt (IRQ)
- Section 19. Keyboard Interrupt Module (KBI)
- Section 20. Computer Operating Properly (COP)
- Section 21. Low-Voltage Inhibit (LVI)
- Section 22. Break Module (BRK)
- Section 23. Electrical Specifications
- 23.1 Contents
- 23.2 Introduction
- 23.3 Absolute Maximum Ratings
- 23.4 Functional Operating Range
- 23.5 Thermal Characteristics
- 23.6 5.0-V DC Electrical Characteristics
- 23.7 EEPROM and Memory Characteristics
- 23.8 5.0-V Control Timing
- 23.9 Timer Interface Module Characteristics
- 23.10 ADC Characteristics
- 23.11 SPI Characteristics
- 23.12 Clock Generation Module Characteristics
- 23.13 FLASH Memory Characteristics
- Section 24. Mechanical Specifications
- Section 25. Ordering Information
Serial Communications Interface
Technical Data MC68HC908AB32 — Rev. 1.1
258 Serial Communications Interface Module (SCI) Freescale Semiconductor
SCI receiver full bit, SCRF. The idle line type bit, ILTY, determines
whether the receiver begins counting logic 1s as idle character bits
after the start bit or after the stop bit.
NOTE: With the WAKE bit clear, setting the RWU bit after the RxD pin has been
idle may cause the receiver to wake up immediately.
15.5.3.7 Receiver Interrupts
The following sources can generate CPU interrupt requests from the SCI
receiver:
• SCI receiver full (SCRF) — The SCRF bit in SCS1 indicates that
the receive shift register has transferred a character to the SCDR.
SCRF can generate a receiver CPU interrupt request. Setting the
SCI receive interrupt enable bit, SCRIE, in SCC2 enables the
SCRF bit to generate receiver CPU interrupts.
• Idle input (IDLE) — The IDLE bit in SCS1 indicates that 10 or 11
consecutive logic 1s shifted in from the PTE1/RxD pin. The idle
line interrupt enable bit, ILIE, in SCC2 enables the IDLE bit to
generate CPU interrupt requests.
15.5.3.8 Error Interrupts
The following receiver error flags in SCS1 can generate CPU interrupt
requests:
• Receiver overrun (OR) — The OR bit indicates that the receive
shift register shifted in a new character before the previous
character was read from the SCDR. The previous character
remains in the SCDR, and the new character is lost. The overrun
interrupt enable bit, ORIE, in SCC3 enables OR to generate SCI
error CPU interrupt requests.
• Noise flag (NF) — The NF bit is set when the SCI detects noise on
incoming data or break characters, including start, data, and stop
bits. The noise error interrupt enable bit, NEIE, in SCC3 enables
NF to generate SCI error CPU interrupt requests.
