PSB3186FV14NT Infineon Technologies, PSB3186FV14NT Datasheet - Page 113

• Manufacturer Part Number: PSB3186FV14NT
• Manufacturer: Infineon Technologies

Specifications of PSB3186FV14NT

• Number Of Line Interfaces: 1
• Control Interface: HDLC
• Lead Free Status / Rohs Status: Not Compliant

– XDOV (Transmit Data Overflow), indicating that the data block size has been
– XFW (Transmit FIFO Write Enable), indicating that data can be written to the XFIFOD.
Note: The significant interrupts and commands are underlined as only these are usually
The XFIFOD requests service from the microcontroller by setting a bit in the ISTAD
register, which causes an interrupt (XPR, XDU, XMR). The microcontroller can then read
the status register STARD (XFW, XDOV), write data in the FIFO and it can change the
transmit FIFO block size (EXMD.XFBS) if required.
The instant of the initiation of a transmit pool ready (XPR) interrupt after different transmit
control commands is listed in
Table 17
CMDRD Register
XTF
XTF & XME
XME
When setting XME the transmitter appends the CRC and the endflag at the end of the
frame. When XTF & XME has been set, the XFIFOD is locked until successful
transmission of the current frame, so a consecutive XPR interrupt also indicates
successful transmission of the frame whereas after XME or XTF the XPR interrupt is
asserted as soon as there is space for one data block in the XFIFOD.
The transfer block size is 32 bytes for D- and B-channel by default, but sometimes, if the
microcontroller has a high computational load, it is useful to increase the maximum
reaction time for an XPR interrupt. However, the threshold can only be changed for
D-channel. The maximum reaction time is:
t
With a selected block size of 16 bytes an XPR interrupt indicates when a transmit FIFO
space of at least 16 bytes is available to accept further data, i.e. there are still a maximum
of 48 bytes (64 bytes - 16 bytes) to be transmitted. With a 32 bytes block size the XPR
is initiated when a transmit FIFO space of at least 32 bytes is available to accept further
data, i.e. there are still a maximum of 32 bytes (64 bytes - 32 bytes) to be transmitted.
The maximum reaction time for the smaller block size is 50 % higher with the trade-off
of a doubled interrupt load. With a selected block size an XPR always indicates the
Data Sheet
max
exceeded, i.e. more than 16 or 32 byte were entered and data was overwritten.
This status flag may be polled instead of or in addition to XPR.
= (XFIFOD size - XFBS) / data transmission rate
used during a normal transmission sequence.
XPR Interrupt (availability of XFIFOD) after XTF, XME Commands
Transmit pool ready (XPR) interrupt initiated ...
as soon as the selected buffer size in the XFIFOD is available.
after the successful transmission of the closing flag.
The transmitter always sends an abort sequence.
as soon as the selected buffer size in the FIFO is available, two
consecutive frames share flags.
Table
17.
113
Description of Functional Blocks
ISAC-SX TE
PSB 3186
2003-01-30