ADSP-BF532SBB400 Analog Devices Inc, ADSP-BF532SBB400 Datasheet - Page 17

• Manufacturer Part Number: ADSP-BF532SBB400
• Description: IC DSP CTLR 16BIT 400MHZ 169-BGA
• Manufacturer: Analog Devices Inc
• Series: Blackfin®r
• Type: Fixed Pointr

Specifications of ADSP-BF532SBB400

• Interface: SPI, SSP, UART
• Clock Rate: 400MHz
• Non-volatile Memory: ROM (1 kB)
• On-chip Ram: 84kB
• Voltage - I/o: 1.8V, 2.5V, 3.3V
• Voltage - Core: 1.20V
• Operating Temperature: -40°C ~ 85°C
• Mounting Type: Surface Mount
• Package / Case: 169-BGA
• For Use With: ADZS-BF533-EZLITE - KIT W/BOARD EVAL FOR ADSP-BF533
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant

Silicon Anomaly List
30.
31.
DESCRIPTION:
In asynchronous communications, transmitter and receiver bit clocks can differ to a certain percentage of the nominal value. The exact
amount is dependent upon the configuration of the word to be transmitted and other external factors such as signal quality.
For the Blackfin UART receiver, the tolerance is different when its bit-clock is slower or faster than the sender's clock. The Blackfin UART
receiver will tolerate differences well when the transmitting side (sender) is operating at slightly lower bit rates. If, however, the sender is
operating at slightly higher bit rates than the Blackfin receiver, the communication may fail for back-to-back transfers (i.e. no gaps
between the words).
The reason for this is that the receiver, as per the standard implementation, samples the stop-bit, like any other bit, 16 times before it is
ready to detect a new start bit condition. Since the decision of whether a stop-bit has been detected is done after the 9th sample, the
receiver should immediately be ready for the next word if a stop-bit is detected. Instead, the Blackfin receiver will take the remaining 7
samples as well.
The effect of this is that the sampling error may accumulate for the kind of data transfers described above.
The anomaly has no effect on single transfers or transfers with gaps between the words, as the sampling error will not accumulate.
WORKAROUND:
The sender should operate at a lower (or identical) bit-rate.
If this cannot be guaranteed (and if possible), configure the sender to transmit more than one stop-bit, thus inserting the necessary gaps
between words.
If both the sender and the receiver are Blackfin devices in a bidirectional communication channel, the above workarounds will not resolve
this issue. This is due to anomalies 05000225 and 05000231.
APPLIES TO REVISION(S):
0.3, 0.4
DESCRIPTION:
The STB bit controls how many stop-bits are generated by the transmitter.
However, this setting also incorrectly affects how many stop-bits are sampled by the receiver. The correct behavior is for the receiver to
always sample and test one stop-bit. However, the receiver will sample and test the number of stop-bits set by the STB bit. This incorrect
behavior also affects framing error detection.
Note that this anomaly makes the workaround for anomaly 05000230 not applicable to the case of a bidirectional link composed of two
Blackfin devices.
WORKAROUND:
None
APPLIES TO REVISION(S):
0.3, 0.4
05000230 - UART Receiver is Less Robust Against Baudrate Differences in Certain Conditions:
05000231 - UART STB Bit Incorrectly Affects Receiver Setting:
NR003532D | Page 17 of 45 | July 2008
ADSP-BF531/BF532/BF533