Control Registers
1189
SPNU503C – March 2018
Copyright © 2018, Texas Instruments Incorporated
Multi-Buffered Serial Peripheral Interface Module (MibSPI) with Parallel Pin
Option (MibSPIP)
24.9.26 Multi-buffer Mode Enable Register (MIBSPIE)
NOTE:
Accessibility of Multi-Buffer RAM
The multi-buffer RAM is not accessible unless the MSPIENA bit set to 1. The only exception
to this is in test mode, where, by setting RXRAMACCESS to 1, the multi-buffer RAM can be
fully accessed for both read and write.
Figure 24-55. Multi-buffer Mode Enable Register (MIBSPIE) [offset = 70h]
31
17
16
Reserved
RXRAM_ACCESS
R-0
R/WP-0
15
1
0
Reserved
MSPIENA
R-0
R/WP-0
LEGEND: R/W = Read/Write; R = Read only; WP = Write in privilege mode only; -
n
= value after reset
Table 24-34. Multi-buffer Mode Enable Register (MIBSPIE) Field Descriptions
Bit
Field
Value
Description
31-17
Reserved
0
Reads return 0. Writes have no effect.
16
RXRAM ACCESS
Receive-RAM access control. During normal operating mode of SPI, the receive data/status
portion of multi-buffer RAM is read-only. To enable testing of receive RAM, direct read/write
access is enabled by setting this bit.
0
The RX portion of multi-buffer RAM is not writable by the CPU.
1
The whole of multi-buffer RAM is fully accessible for read/write by the CPU.
Note: The RX RAM ACCESS bit remains 0 after reset and it should remain cleared to 0 at
all times, except when testing the RAM. SPI should be given a local reset by using the
nRESET (SPIGCR0[0]) bit after RAM testing is performed so that the multi-buffer RAM
gets re-initialized.
15-1
Reserved
0
Reads return 0. Writes have no effect.
0
MSPIENA
Multi-buffer mode enable. After power-up or reset, MSPIENA remains cleared, which means
that the SPI runs in compatibility mode by default. If multi-buffer mode is desired, this register
should be configured first after configuring the SPIGCR0 register. If MSPIENA is not set to 1,
the multi-buffer mode registers are not writable.
0
The SPI runs in compatibility mode, that is, in this mode the MibSPI is fully code-compliant to
the standard device SPI. No multi-buffered-mode features are supported.
1
The SPI is configured to run in multi-buffer mode.
NOTE:
Accessibility of Registers
Registers from this offset address onwards are not accessible in SPI compatibility mode.
They are accessible only in the multi-buffer mode.