GR740-UM-DS, Nov 2017, Version 1.7
334
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GR740
24.3.3 Event register
Table 422.
0x24 - EVENT - Event register
31 30
15 14 13 12 11 10
9
8
7
0
TIP
RESERVED
LT R OV UN M
M
E
NE NF
RESERVED
0
0
0
0
0
0
0
0
0
0
r
r
wc
r
wc wc wc
r
r
r
31
Transfer in progress (TIP) - This bit is ‘1’ when the core has a transfer in progress. Writes have no
effect. This bit is set when the core starts a transfer and is reset to ‘0’ once the core considers the
transfer to be finished. Behavior affected by setting of CITE field in Mode register.
30: 15
RESERVED (R) - Read as zero and should be written to zero to ensure forward compatibility.
14
Last character (LT) - This bit is set when a transfer completes if the transmit queue is empty and the
LST bit in the Command register has been written. This bit is cleared by writing ‘1’, writes of ‘0’
have no effect.
13
RESERVED (R) - Read as zero and should be written to zero to ensure forward compatibility.
12
Overrun (OV) - This bit gets set when the receive queue is full and the core receives new data. The
core continues communicating over the SPI bus but discards the new data. This bit is cleared by writ-
ing ‘1’, writes of ‘0’ have no effect.
11
Underrun (UN) - This bit is only set when the core is operating in slave mode. The bit is set if the
core’s transmit queue is empty when a master initiates a transfer. When this happens the core will
respond with a word where all bits are set to ‘1’. This bit is cleared by writing ‘1’, writes of ‘0’ have
no effect.
10
Multiple-master error (MME) - This bit is set when the core is operating in master mode and the SPI-
SEL input goes active. In addition to setting this bit the core will be disabled. This bit is cleared by
writing ‘1’, writes of ‘0’ have no effect.
9
Not empty (NE) - This bit is set when the receive queue contains one or more elements. It is cleared
automatically by the core, writes have no effect.
8
Not full (NF) - This bit is set when the transmit queue has room for one or more words. It is cleared
automatically by the core when the queue is full, writes have no effect. This field is only updated
when the core is enabled (EN field of Mode register is set to ’1’).
7: 0
RESERVED (R) - Read as zero and should be written to zero to ensure forward compatibility.