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ME 4447/6405. Microprocessor Control of Manufacturing Systems and Introduction to Mechatronics Instructor: Professor Charles Ume Lecture #7. Product Family and Designations. RAM – Random Access Memory “Volatile” – loses contents after power off ROM – Read Only Memory “non-Volatile”
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ME 4447/6405 Microprocessor Control of Manufacturing Systems and Introduction to Mechatronics Instructor: Professor Charles Ume Lecture #7
RAM – Random Access Memory • “Volatile” – loses contents after power off • ROM – Read Only Memory • “non-Volatile” • Contents must be programmed at the factory • EPROM – Electrically Programmable Read Only Memory • “non-Volatile” • Electrically programmable • May be erasable with ultraviolet light if manufacturer included window in chip package • Still considered Read Only Memory during normal program execution • EEPROM – Electrically Erasable Programmable Read Only Memory • “non-Volatile” • Electrically programmable and erasable (Note:Sometimes higher voltage than microcontroller voltage may be required) • Slower to write to than RAM so still considered Read Only Memory during normal program execution
Product Designations found in literature is shown below: Read:MC9S12C32 Device User Guide V01.14 HCS12 Microcontrollers: MC9S12C128 Rev 01.23
MC9S12C package options and block diagram
MC9S12C-Family package options: • 48-pin Low-profile Quad Flat Package (LQFP) • 52-pin Low-profile Quad Flat Package • 80-pin quad flat package (QFP) (Shown)
MC9S12C-Family Block Diagram shows available subsystems Figure1-1. MC9S12C-Family Block Diagram
Data Direction and Data Register Data Direction Register (DDR) Used to indicate direction of data flow in a port Example configure pins 0, 3, 5 and 7 of port A as output pins Note: By default all port pins are input pins DDRA ($0002)should be loaded with: #%10101001 or #$A9 Assembly code to accomplish the above: LDAA #$A9 STAA $0002 Data Register Used to control state of devices connected to output pins Used to determine state of devices connected to input pins Suppose 4 different light bulbs are to be turned on and off from these output pins:
Data Direction and Data Register • Port A data Register address is $0000 • To turn light bulbs connected to PA0 and PA3 on: • Store #%00001001 or #$09 at address $0000 • LDAA #$09 • STAA $0000 • To turn all light bulbs connected to PA0, PA3, PA5 and PA7 on: • Store #%10101001 or #$A9 at address $0000 LDAA #$A9 STAA $0000
Data Direction and Data Register Suppose you want to determine state of machines connected to input pins PA1, PA2, PA4 and PA6: You load accumulator A with content of address $0000 In accumulator A: If logic 1 is written in bits 1 and 4 respectively: That will mean that devices connected to PA1 and PA4 have been turned on In accumulator A: If logic 1 is written in bits 1, 2, 4 and 6: That will mean that all devices connected to PA1, PA2, PA4 and PA6 are on
. . . Figure 6. Register and Control Bit Assignments (Programming Reference) Excerpt of Detailed Register Map (Device User Guide)
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MC9S12C-Family hardware mode selection, hardware mode connections, and hardware mode memory maps
Hardware Mode Selection Summary (Reference Manual) MODA, MODB, & MODC may be writable in software after startup, see Reference
HCS12 Features • 80 pin HCS12 • Crystal Frequency is 16 Mhz • Clock Frequency is 8 Mhz Therefore, 1 clock cycle = 0.125micro seconds • Normal Expanded Wide
Hardware Mode External Connections • In Single Chip mode, Ports A, B and E available as general purpose input/output pins • In Narrow Expanded Mode, Ports A and B form 16-bit Address and 8-bit Data bus, Port E provides control signals for external devices • In Wide Expanded mode, Ports A and B form 16-bit Address and 16-bit Data bus, Port E provides control signals for external devices
Axiom CML-12C32 memory maps & interrupt vectors
Axiom CML-12C32 Evaluation Board MC9S12C32 Solderless Breadboard Serial Port Oscillator Power Jack Address Demultiplexer Reset MCU Port External SRAM
Default Configuration: • MODC = 1 • MODA = MODB = 0 Single Chip Mode • MODA and MODB may be changed in software to permit use of Expanded Wide mode once after each reset • Internal Flash Memory is available only if ROMON is enabled • At the rising edge of Reset, the state of pin PP[6]/KWP[6]/ROMCTL is latched to the ROMON bit. • ROMCTL = 1 ROMON Enabled, Flash memory available • ROMCTL = 0 ROMON Disable, Flash memory unavailable • For operation in this class, ROMON will be Enabled, so do not pull PP[6] low on Reset!
Axiom CML-C32 • Single chip mode • ROMON Enabled • MON12 not in use • (CodeWarrior) • MODA = 0 • MODB = 0 • Internal User RAM available: • $0800-$0FFF • User can put a program in Internal Flash$8000-$FEFF • Ports A and B available for use
Axiom CML-C32 • Single chip mode • ROMON Enabled • MON12 in use • MODA = 0; MODB = 0 • Internal User RAM available: • $0800-$0DFF • Stack Location: $0E00 – $0E5F • Mon12 RAM Interrupt Vector: $0F8A – 0FFF • User can put a program in Internal Flash $8000-$BEFF and Internal RAM • Ports A and B available for use MON12 is located here
Axiom CML-C32 • Expanded Wide mode • ROMON Enabled • MON12 not in use(CodeWarrior) • MODA = 1 • MODB = 1 • Internal User RAM available: • $0800-$0FFF • External User RAM available: • $0400-$07FF • $1000-$7FFF • User can put a program in Internal Flash $8000-$FEFF • Ports A and B NOT available for use
Axiom CML-C32 • Expanded Wide mode • ROMON Enabled • MON12 in use • MODA = 1; MODB = 1 • Internal User RAM available: • $0800-$0DFF (Run AXIDE) • Monitor Utility Jump Table: • $FF10-$FF67 • External User RAM available: • $0400-$07FF • $1000-$7FFF • User can put a program in Internal Flash $8000-$B7FF and RAM • Ports A and B NOT available for use • Stack Location: $0E00 – $0E5F • Mon12 RAM Interrupt Vector: • $0F8A – 0FFF MON12 is located here MON12 is located here
Interrupt Vector Table • Mon12 NOT in use • Standard S12C32 Interrupt Jump Table • Each vector is 2 bytes. User stores address of interrupt service routine in appropriate vector • 0x is same as $: It is used when writing program in C
Interrupt Vector Table • Mon12 NOT in use • Standard S12C32 Interrupt Jump Table • Each vector is 2 bytes. User stores address of interrupt service routine in appropriate vector
Standard S12C32 Interrupt Jump Table (MON12 not in use) The user can put the starting address of his/her subroutine Directly in the vector field of the interrupt he/she wants to Use. Example: If the user wants to use the IRQ interrupt, he/she can put the starting address of his/her subroutine directly in vector fields $FFF2 and $FFF3
Interrupt Vector Table • MON12 in use • Standard S12C32 Interrupt Vector Jump Table is not available with MON12 • MON12 supplies alternate Interrupt Jump Table • User’s interrupt service routine must be stored in $4000-$7FFF (External RAM) if Autostart is to be used Monitor Interrupt Vector Table (CML-C32 User’s Guide)
Interrupt Vector Table • MON12 in use • Standard S12C32 Interrupt Vector Jump Table is not available with MON12 • MON12 supplies alternate Interrupt Jump Table • User’s interrupt service routine must be stored in $4000-$7FFF if Autostart is to be used Monitor Interrupt Vector Table (CML-C32 User’s Guide) To use the vector table, the user again writes the address of the interrupt service routine to the location given in the table. For example, to use the IRQ interrupt to call an interrupt service routine located at address ISR_ADDR, the user writes the following code: MOVW #$0800, $0FF2 OR MOVW #ISR_ADDR,$0FF2 LDD #$0800 STD $0FF2 During initialization MON12 writes $0000 to all vectors in the Monitor Interrupt vector Table to cause any unscheduled interrupt to cause a trap. Any nonzero value will cause the S12C32 to jump to the interrupt service routine located at that value.
Relationship Between Standard S12C32 Interrupt Vectors and MON12 Interrupt Table Vectors When MON12 is in use, it configures the standard interrupt vector table and the user may not override these values. MON12 allocates memory for the Monitor Interrupt Table, located from $0F8A - $0FFF. During initialization, MON12 clears the contents of the Monitor Interrupt Table. If an interrupt occurs and the corresponding vector contains $0000, MON12 perceives this as an error and restarts the monitor program, ending execution of user code. MON12 uses some interrupts to accomplish its tasks, hence uses those vector addresses. In addition, the standard interrupt table is located in Flash EEPROM and cannot be written to using MON12. When writing programs in C, a BDM cable is used to program the HCS12 and the standard interrupt table is used.
Several subroutines from Mon12 exist that are available for performing I/O tasks. Utility subroutines available to the user are as follows:
Assume an interrupt is enabled in the main program, e.g. IRQ Signal is received by the MC from IRQ pin MC will finishing executing the current instructions I-bit in the CCR is set to 1 (this will cause any incoming maskable interrupt to queue up) CPU registers are pushed in the Stack Starting address of the interrupt Sub-routine to be executed is fetched from the IRQ vectors This Sub-routine is executed and the last instruction is RTI The execution of the RTI will cause all the data in the Stack to be pulled out and put back in their respective registers The last 2-byte data pulled out are the Program Counter High and Low bytes address The MC will use these 2-byte address to know where to get the next instruction to be executed Interrupt Acknowledgement