ST72F324BJ6B6 STMicroelectronics, ST72F324BJ6B6 Datasheet - Page 103

• Manufacturer Part Number: ST72F324BJ6B6
• Description: MCU 8BIT 32KB FLASH/ROM 42-SDIP
• Manufacturer: STMicroelectronics
• Series: ST7r

Specifications of ST72F324BJ6B6

• Core Processor: ST7
• Core Size: 8-Bit
• Speed: 8MHz
• Connectivity: SCI, SPI
• Peripherals: LVD, POR, PWM, WDT
• Number Of I /o: 32
• Program Memory Size: 32KB (32K x 8)
• Program Memory Type: FLASH
• Ram Size: 1K x 8
• Voltage - Supply (vcc/vdd): 3.8 V ~ 5.5 V
• Data Converters: A/D 12x10b
• Oscillator Type: Internal
• Operating Temperature: -40°C ~ 85°C
• Package / Case: 42-SDIP (0.600", 15.24mm)
• Controller Family/series: ST7
• No. Of I/o's: 32
• Ram Memory Size: 1KB
• Cpu Speed: 8MHz
• No. Of Timers: 2
• Embedded Interface Type: SCI, SPI
• No. Of Pwm Channels: 3
• Processor Series: ST72F3x
• Core: ST7
• Data Bus Width: 8 bit
• Data Ram Size: 1 KB
• Interface Type: SCI, SPI
• Maximum Clock Frequency: 8 MHz
• Number Of Programmable I/os: 32
• Number Of Timers: 3
• Maximum Operating Temperature: + 85 C
• Mounting Style: Through Hole
• Development Tools By Supplier: ST7232X-EVAL, ST7MDT20-DVP3, ST7MDT20J-EMU3, STX-RLINK
• Minimum Operating Temperature: - 40 C
• On-chip Adc: 10 bit, 12 Channel
• For Use With: 497-6421 - BOARD EVAL DGTL BATT CHGR DESIGN497-5046 - KIT TOOL FOR ST7/UPSD/STR7 MCU
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• Eeprom Size: -
• Lead Free Status / Rohs Status: Details
• Other names: 497-5589-5

ST72324Bxx
Figure 55. Clearing the WCOL bit (Write collision flag) software sequence
Single master systems
A typical single master system may be configured, using an MCU as the master and four
MCUs as slaves (see
The master device selects the individual slave devices by using four pins of a parallel port to
control the four SS pins of the slave devices.
The SS pins are pulled high during reset since the master device ports will be forced to be
inputs at that time, thus disabling the slave devices.
Note: To prevent a bus conflict on the MISO line the master allows only one active slave
device during a transmission.
For more security, the slave device may respond to the master with the received data byte.
Then the master will receive the previous byte back from the slave device if all MISO and
MOSI pins are connected and the slave has not written to its SPIDR register.
Other transmission security methods can use ports for handshake lines or data bytes with
command fields.
Figure 56. Single master/multiple slave configuration
2nd Step
Clearing sequence after SPIF = 1 (end of a data byte transfer)
Clearing sequence before SPIF = 1 (during a data byte transfer)
1st Step
5V
SCK
SCK
MOS
SS
MOSI
Read SPICSR
Read SPIDR
Maste
MCU
I
Slave
MCU
Figure
MISO
MISO
r
1st Step
2nd Step
SS
56).
WCOL = 0
SPIF = 0
Result
Read SPICSR
Read SPIDR
SCK
MOSI
MCU
Slave
MISO
SS
WCOL = 0
Result
SCK
MOSI
Slave
MCU
MISO
SS
Note: Writing to the SPIDR register
instead of reading it does not reset
the WCOL bit.
On-chip peripherals
SCK
MOSI
Slave
MCU
MISO
SS
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