S9S12XS256J0CAL Freescale Semiconductor, S9S12XS256J0CAL Datasheet - Page 148

• Manufacturer Part Number: S9S12XS256J0CAL
• Description: MCU 256K FLASH 112-LQFP
• Manufacturer: Freescale Semiconductor
• Series: HCS12r

Specifications of S9S12XS256J0CAL

• Core Processor: HCS12X
• Core Size: 16-Bit
• Speed: 40MHz
• Connectivity: CAN, SCI, SPI
• Peripherals: LVD, POR, PWM, WDT
• Number Of I /o: 91
• Program Memory Size: 256KB (256K x 8)
• Program Memory Type: FLASH
• Eeprom Size: 8K x 8
• Ram Size: 12K x 8
• Voltage - Supply (vcc/vdd): 1.72 V ~ 5.5 V
• Data Converters: A/D 16x12b
• Oscillator Type: External
• Operating Temperature: -40°C ~ 85°C
• Package / Case: 112-LQFP
• Processor Series: S12XS
• Core: HCS12
• Data Bus Width: 16 bit
• Data Ram Size: 12 KB
• Interface Type: CAN, SCI, SPI
• Maximum Clock Frequency: 40 MHz
• Number Of Programmable I/os: 91
• Number Of Timers: 12
• Maximum Operating Temperature: + 85 C
• Mounting Style: SMD/SMT
• 3rd Party Development Tools: EWHCS12
• Development Tools By Supplier: DEMO9S12XSFAME, EVB9S12XEP100
• Minimum Operating Temperature: - 40 C
• On-chip Adc: 12 bit, 16 Channel
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant

Memory Mapping Control (S12XMMCV4)
3.4.3.1
The arbitration scheme allows only one master to be connected to a target at any given time. The following
rules apply when prioritizing accesses from different masters to the same target bus:
3.5
3.5.1
CALL and RTC instructions are uninterruptible CPU instructions that automate page switching in the
program page window. The CALL instruction is similar to the JSR instruction, but the subroutine that is
called can be located anywhere in the local address space or in any Flash or ROM page visible through the
program page window. The CALL instruction calculates and stacks a return address, stacks the current
PPAGE value and writes a new instruction-supplied value to the PPAGE register. The PPAGE value
controls which of the 256 possible pages is visible through the 16KB program page window in the 64KB
local CPU memory map. Execution then begins at the address of the called subroutine.
During the execution of the CALL instruction, the CPU performs the following steps:
This sequence is uninterruptible. There is no need to inhibit interrupts during the CALL instruction
execution. A CALL instruction can be performed from any address to any other address in the local CPU
memory space.
The PPAGE value supplied by the instruction is part of the effective address of the CPU. For all addressing
mode variations (except indexed-indirect modes) the new page value is provided by an immediate operand
in the instruction. In indexed-indirect variations of the CALL instruction a pointer specifies memory
locations where the new page value and the address of the called subroutine are stored. Using indirect
addressing for both the new page value and the address within the page allows usage of values calculated
at run time rather than immediate values that must be known at the time of assembly.
The RTC instruction terminates subroutines invoked by a CALL instruction. The RTC instruction unstacks
the PPAGE value and the return address and refills the queue. Execution resumes with the next instruction
after the CALL instruction.
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1. Writes the current PPAGE value into an internal temporary register and writes the new instruction-
2. Calculates the address of the next instruction after the CALL instruction (the return address) and
3. Pushes the temporarily stored PPAGE value onto the stack
4. Calculates the effective address of the subroutine, refills the queue and begins execution at the new
CPU always has priority over BDM .
BDM has priority over CPU when its access is stalled for more than 128 cycles. In the later case
the suspect master will be stalled after finishing the current operation and the BDM will gain access
to the bus.
supplied PPAGE value into the PPAGE register
pushes this 16-bit value onto the stack
address
Initialization/Application Information
CALL and RTC Instructions
Master Bus Prioritization regarding access conflicts on Target Buses
S12XS Family Reference Manual, Rev. 1.11
Freescale Semiconductor