SAB82538 Datasheet, PDF (109/253 Pages) Infineon Technologies AG – ICs for Communications

SAB 82538
SAF 82538
Table 8
Status Information after RME Interrupt
Length of message (bytes)
Address combination and/or
Address field
Control field
Type of frame (COMMAND / RESPONSE)
CRC result (good / bad)
Valid frame (yes / no)
ABORT sequence recognized (yes / no)
Data overflow
⇒ RBCH, RBCL
⇒ RSTA
⇒ RAL1
⇒ RHCR
⇒ RSTA
⇒ RSTA
⇒ RSTA
⇒ RSTA
⇒ RSTA
register
RFIFO: last byte
RFIFO
RFIFO
RFIFO: last byte
RFIFO: last byte
RFIFO: last byte
RFIFO: last byte
RFIFO: last byte
ASYNC, BISYNC
q RPF (Receive Pool Full) interrupt, indicating that a specified number of bytes (refer to
register RFC) can be read from RFIFO.
q TCD (Termination Character Detected) interrupt, indicating that reception has been
terminated by reception of a specified character (refer to register TCR and bit
RFC.TCDE).
Additionally, the CPU can have access to contents of RFIFO without having received an
interrupt (and thereby causing TCD to occur) by issuing the RFIFO Read command
(CMDR.RFRD).
In addition to every received character the assigned status information Parity bit (0/1),
Parity Error (yes/no), Framing Error (yes/no, ASYNC only!) is optionally stored in RFIFO.
In addition to the end conditions (TCD interrupt or after RFRD command) the length of
the last received data block is stored in register RBCL.
Note: For all serial modes! After the received data has been read from the RFIFO, this
must be explicitly acknowledged by the CPU issuing a RMC (Receive Message
Complete) command. The CPU has to handle the RPF interrupt before additional
32 bytes are received via the serial interface which would cause a “Receive Data
Overflow” condition.
The following figure gives an example of an interrupt controlled reception sequence,
assuming that a “long” frame (66 bytes) followed by two short frames (6 bytes each) is
received.
Semiconductor Group
109