FRCTL_A Registers
305
SLAU367P – October 2012 – Revised April 2020
Copyright © 2012–2020, Texas Instruments Incorporated
FRAM Controller A (FRCTL_A)
8.6.1 FRCTL0 Register (Offset = 0h) [reset = 9600h]
FRCTL0 is shown in
and described in
.
Return to
FRAM Controller A Control Register 0
Figure 8-3. FRCTL0 Register
15
14
13
12
11
10
9
8
FRCTLPW
R/W-96h
7
6
5
4
3
2
1
0
NWAITS
AUTO
Reserved
WPROT
R/W-0h
R/W-0h
R-0h
R/W-0h
Table 8-4. FRCTL0 Register Field Descriptions
Bit
Field
Type
Reset
Description
15-8
FRCTLPW
R/W
96h
FRCTLPW password. Always read as 96h.
Note:
The correct password (A5h) is written to the FRCTLPW bits by
the bootcode during the device boot-up process; therefore, the
FRCTL0 (low byte), GCCTL0, and GCCTL1 registers are unlocked
after the device is powered up or reset (BOR) or after LPMx.5
wakeup.
96h (R) = FRPW : Read value while locked
A5h (W) = FWPW : Must be written as A5h or a PUC is generated
on word write. After a correct password is written and register
access is enabled, a wrong password write in byte mode disables
the access and no PUC is generated.
7-4
NWAITS
R/W
0h
Wait state generator access time control when AUTO =0.
Each wait state adds a N integer multiple increase of the IFCLK
period where N = 0 through 15. N = 0 implies no wait states. When a
timing violation is detected, the Access Time Error Flag (ACCTEIFG)
is set and the maximum wait state, 15, is automatically applied to the
NWAITS[3:0] to avoid further timing violation. While the ACCTEIFG
bit is set, the NWAIS[3:0] cannot be overwritten and writing to the
FRAM memory is prohibited regardless of the WPROT bit. Only
reading is allowed. The ACCTEIFG bit must be cleared prior to
applying a new value to NWAITS[3:0] or writing access to the FRAM
memory. The timing violation (ACCTEIFG) can generate a system
NMI (SYSNMI) if the Access Time Error Interrupt Enable (ACCTEIE)
bit is set. When a timing violation occurs for reading, the data from
FRAM memory could be incorrect, thus proper error handling is
recommended before proceeding.
Reset type: BOR
0h (R/W) = FRAM wait states: 0
1h (R/W) = FRAM wait states: 1
2h (R/W) = FRAM wait states: 2
3h (R/W) = FRAM wait states: 3
4h (R/W) = FRAM wait states: 4
5h (R/W) = FRAM wait states: 5
6h (R/W) = FRAM wait states: 6
7h (R/W) = FRAM wait states: 7
8h (R/W) = FRAM wait states: 8
9h (R/W) = FRAM wait states: 9
Ah (R/W) = FRAM wait states: 10
Bh (R/W) = FRAM wait states: 11
Ch (R/W) = FRAM wait states: 12
Dh (R/W) = FRAM wait states: 13
Eh (R/W) = FRAM wait states: 14
Fh (R/W) = FRAM wait states: 15