D12312SVTE25 Renesas Electronics America, D12312SVTE25 Datasheet - Page 214

• Manufacturer Part Number: D12312SVTE25
• Description: MCU 3V 0K 100-TQFP
• Manufacturer: Renesas Electronics America
• Series: H8® H8S/2300r

Specifications of D12312SVTE25

• Core Processor: H8S/2000
• Core Size: 16-Bit
• Speed: 25MHz
• Connectivity: SCI, SmartCard
• Peripherals: POR, PWM, WDT
• Number Of I /o: 70
• Program Memory Type: ROMless
• Ram Size: 8K x 8
• Voltage - Supply (vcc/vdd): 2.7 V ~ 3.6 V
• Data Converters: A/D 8x10b; D/A 2x8b
• Oscillator Type: Internal
• Operating Temperature: -20°C ~ 75°C
• Package / Case: 100-TQFP, 100-VQFP
• Lead Free Status / RoHS Status: Contains lead / RoHS non-compliant
• Eeprom Size: -
• Program Memory Size: -
• Other names: HD6412312SVTE25; HD6412312SVTE25

Section 6 Bus Controller
6.7.5
Do not set MSTPCR to H'FFFF or H'EFFF, since the external bus release function will halt if a
transition is made to sleep mode when either of these settings has been made.
6.8
6.8.1
The chip has a bus arbiter that arbitrates bus master operations.
There are two bus masters, the CPU and DTC, which perform read/write operations when they
have possession of the bus. Each bus master requests the bus by means of a bus request signal.
The bus arbiter determines priorities at the prescribed timing, and permits use of the bus by means
of a bus request acknowledge signal. The selected bus master then takes possession of the bus and
begins its operation.
6.8.2
The bus arbiter detects the bus masters' bus request signals, and if the bus is requested, sends a bus
request acknowledge signal to the bus master making the request. If there are bus requests from
more than one bus master, the bus request acknowledge signal is sent to the one with the highest
priority. When a bus master receives the bus request acknowledge signal, it takes possession of the
bus until that signal is canceled.
The order of priority of the bus masters is as follows:
An internal bus access by an internal bus master and external bus release, can be executed in
parallel.
In the event of simultaneous external bus release request and internal bus master external access
request generation, the order of priority is as follows:
Rev.7.00 Feb. 14, 2007 page 180 of 1108
REJ09B0089-0700
Usage Note
Bus Arbitration
Overview
Operation
(High) DTC > CPU (Low)
(High) External bus release > Internal bus master external access (Low)