ST72F321BAR6T6 STMicroelectronics, ST72F321BAR6T6 Datasheet - Page 93
![MCU 8BIT 32KB FLASH/ROM 64-LQFP](/photos/12/15/121504/stmicroelectronics-64-lqfp_sml.jpg)
ST72F321BAR6T6
Manufacturer Part Number
ST72F321BAR6T6
Description
MCU 8BIT 32KB FLASH/ROM 64-LQFP
Manufacturer
STMicroelectronics
Series
ST7r
Datasheet
1.ST72F321BK6T6.pdf
(187 pages)
Specifications of ST72F321BAR6T6
Core Processor
ST7
Core Size
8-Bit
Speed
8MHz
Connectivity
I²C, SCI, SPI
Peripherals
LVD, POR, PWM, WDT
Number Of I /o
48
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 16x10b
Oscillator Type
Internal
Operating Temperature
-40°C ~ 85°C
Package / Case
64-LQFP
Processor Series
ST72F3x
Core
ST7
Data Bus Width
8 bit
Data Ram Size
1 KB
Interface Type
I2C, SCI, SPI
Maximum Clock Frequency
8 MHz
Number Of Programmable I/os
48
Number Of Timers
2
Maximum Operating Temperature
+ 85 C
Mounting Style
SMD/SMT
Development Tools By Supplier
ST7232X-EVAL, ST7232X-SK/RAIS, ST72321B-D/RAIS, ST7MDT20-DVP3, ST7MDT20J-EMU3, ST7MDT20M-EMU3, STX-RLINK
Minimum Operating Temperature
- 40 C
On-chip Adc
10 bit, 16 Channel
For Use With
497-5046 - 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
497-5582
Available stocks
Company
Part Number
Manufacturer
Quantity
Price
Company:
Part Number:
ST72F321BAR6T6
Manufacturer:
STMicroelectronics
Quantity:
10 000
SERIAL PERIPHERAL INTERFACE (Cont’d)
10.5.5 Error Flags
10.5.5.1 Master Mode Fault (MODF)
Master mode fault occurs when the master device
has its SS pin pulled low.
When a Master mode fault occurs:
Clearing the MODF bit is done through a software
sequence:
1. A read access to the SPICSR register while the
2. A write to the SPICR register.
Notes: To avoid any conflicts in an application
with multiple slaves, the SS pin must be pulled
high during the MODF bit clearing sequence. The
SPE and MSTR bits may be restored to their orig-
inal state during or after this clearing sequence.
Hardware does not allow the user to set the SPE
and MSTR bits while the MODF bit is set except in
the MODF bit clearing sequence.
10.5.5.2 Overrun Condition (OVR)
An overrun condition occurs, when the master de-
vice has sent a data byte and the slave device has
Figure 59. Clearing the WCOL bit (Write Collision Flag) Software Sequence
1st Step
2nd Step
– The MODF bit is set and an SPI interrupt re-
– The SPE bit is reset. This blocks all output
– The MSTR bit is reset, thus forcing the device
quest is generated if the SPIE bit is set.
from the device and disables the SPI periph-
eral.
into slave mode.
MODF bit is set.
Clearing sequence after SPIF = 1 (end of a data byte transfer)
Clearing sequence before SPIF = 1 (during a data byte transfer)
1st Step
2nd Step
Read SPICSR
Read SPIDR
RESULT
SPIF =0
WCOL=0
Read SPIDR
Read SPICSR
ST72321BRx, ST72321BARx ST72321BJx, ST72321BKx
RESULT
WCOL=0
not cleared the SPIF bit issued from the previously
transmitted byte.
When an Overrun occurs:
– The OVR bit is set and an interrupt request is
In this case, the receiver buffer contains the byte
sent after the SPIF bit was last cleared. A read to
the SPIDR register returns this byte. All other
bytes are lost.
The OVR bit is cleared by reading the SPICSR
register.
10.5.5.3 Write Collision Error (WCOL)
A write collision occurs when the software tries to
write to the SPIDR register while a data transfer is
taking place with an external device. When this
happens, the transfer continues uninterrupted;
and the software write will be unsuccessful.
Write collisions can occur both in master and slave
mode. See also
Management.
Note: a "read collision" will never occur since the
received data byte is placed in a buffer in which
access is always synchronous with the MCU oper-
ation.
The WCOL bit in the SPICSR register is set if a
write collision occurs.
No SPI interrupt is generated when the WCOL bit
is set (the WCOL bit is a status flag only).
Clearing the WCOL bit is done through a software
sequence (see
generated if the SPIE bit is set.
Note: Writing to the SPIDR regis-
ter instead of reading it does not
reset the WCOL bit
Figure
Section 10.5.3.2 Slave Select
59).
93/187