Motorola MPC8260 - Manual (Page 749)

MOTOROLA Chapter 27. Multi-Channel Controllers (MCCs) 27-19
Part IV. Communications Processor Module
Table 27-13 describes MCCE Þelds.
27.10.1.1 Interrupt Table Entry
Each interrupt table entry, shown in Figure 27-14, contains information about channel-
speciÞc events. The transmit circular table shows only events caused by transmission; the
receive circular tables shows only events caused by reception.
Table 27-13. MCCE/MCCM Register Field Descriptions
Bits Name Description
0 QOV0 QOVxÑReceive interrupt queue overßow. IQOV is set (and an interrupt request generated) by the
CP whenever an overßow occurs in the transmit circular interrupt table. This occurs if the CP tries to
update an interrupt entry that was not handled by the user (such an entry is identiÞed by V = 1).
RINTxÑReceive interrupt. When RINT = 1, the MCC generated at least one new entry in the receive
interrupt circular table. After clearing it, the user reads the next entry from the receive interrupt
circular table and starts processing a speciÞc channelÕs exception. The user returns from the
interrupt handler when it reaches a table entry with V = 0.
1 RINT0
2 QOV1
3 RINT1
4 QOV2
5 RINT2
6 QOV3
7 RINT3
8Р11 С Reserved, should be cleared.
12 TQOV Transmit interrupt queue overßow. TQOV is set (and interrupt request generated) by the CP
whenever an overßow occurs in the transmit circular interrupt table. This condition occurs if the CP
attempts to write a new interrupt entry into an entry that was not handled by the user. Such an entry
is identiÞed by V = 1.
13 TINT Transmit interrupt. When TINT = 1, at least one new entry in the transmit interrupt circular table was
generated by MCC. After clearing it, the user reads the next entry from the transmit interrupt circular
table and starts processing a speciÞc channelÕs exception. The user returns from the interrupt
handler when it reaches a table entry with V = 0.
14 GUN Global transmitter underrun. When set, this ßag indicates that an underrun occured in the MCCÕs
transmitter FIFO buffer. This error is fatal, since it is unknown which channels were affected.
Following the assertion of GUN in the MCCE the MCC stops transmitting data in all channels. The
TDM Tx line becomes idle. The MCC transmitters must be reinitialized after this error. If enabled in
MCCM, an interrupt request is generated when GUN is set. The user must clear GUN.
15 GOV Global receiver overrun. When GOV = 1, an overrun occured in the MCCÕs receiver FIFO buffer. This
error is fatal, since it is unknown which channels were affected. When GOV = 1, the MCC stops
receiving data in all channels. No more data is transferred to memory. The MCC receivers must be
re-initialized after this error. If enabled in MCCM, an interrupt request is generated when GOV is set.
The user must clear GOV bit.