2 spi event/mask registers (spie/spim), Figure 38-7. spie/spim-spi event/mask registers, Table 38-3. spie/spim field descriptions – Freescale Semiconductor MPC8260 User Manual

Page 1255: Spi event/mask registers (spie/spim) -9, Spie/spim—spi event/mask registers -9, Spie/spim field descriptions -9, Example 3, Table 38-3 describes the spie/spim fields

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Serial Peripheral Interface (SPI)

MPC8260 PowerQUICC II Family Reference Manual, Rev. 2

Freescale Semiconductor

38-9

with LEN=7 (data size=8), the following data is selected:

msb

ghij_klmn__opqr_stuv

lsb

the data string is selected:

msb

ghij_klmn__opqr_stuv

lsb

with REV=0, the string transmitted, a byte at a time with lsb first is:

first

nmlk_jihg__vuts_rqpo

last

with REV=1, the string is byte reversed and transmitted, a byte at a time, with lsb

first:

first

ghij_klmn__opqr_stuv

last

Example 3

with LEN=0xC (data size=13), the following data is selected:

msb

ghij_klmn__xxxr_stuv

lsb

the data string selected is:

msb

r_stuv__ghij_klmn

lsb

with REV=0, the string transmitted, a byte at a time with lsb first is:

first

nmlk_jihg__vuts_r

last

with REV=1, the string is half-word reversed:

msb

nmlk_jihg__vuts_r

lsb

and transmitted a byte at a time with lsb first:

first

r_stuv_ghij_klmn

last

38.4.2

SPI Event/Mask Registers (SPIE/SPIM)

The SPI event register (SPIE) generates interrupts and reports events recognized by the SPI. When an
event is recognized, the SPI sets the corresponding SPIE bit. Clear SPIE bits by writing a 1—writing 0 has
no effect. Setting a bit in the SPI mask register (SPIM) enables and clearing a bit masks the corresponding
interrupt. Unmasked SPIE bits must be cleared before the CP clears internal interrupt requests.

Figure 38-7

shows both registers.

Table 38-3

describes the SPIE/SPIM fields.

0

1

2

3

4

5

6

7

Field

MME

TXE

BSY

TXB

RXB

Reset

0000_0000

R/W

R/W

Addr

0x0x11AA6 (SPIE); 0x0x11AAA (SPIM)

Figure 38-7. SPIE/SPIM—SPI Event/Mask Registers

Table 38-3. SPIE/SPIM Field Descriptions

Bits

Name

Description

0–1

Reserved, should be cleared.

2

MME

Multimaster error. Set when SPISEL is asserted externally while the SPI is in master mode.

3

TXE

Tx error. Set when an error occurs during transmission.

4

Reserved, should be cleared.

5

BSY

Busy. Set after the first character is received but discarded because no Rx buffer is available.

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