Motorola ColdFire MCF5281 - Manual (Page 516)

General Purpose I/O Module
26-16 Freescale Semiconductor
26.3.2.5 Port B/C/D Pin Assignment Register (PBCDPAR)
The PBCDPAR controls the pin function of ports B, C, and D.
The PBCDPAR register is read/write.
7 6 5 0
Field PBPA PCDPA —
Reset See Note 1
1
1 Reset state determined during reset configuration as shown in Table 26-8 .
See Note 1 00_0000
R/W: R/W R/W R
Address IPSBAR + 0x10_0050
Figure 26-19. Port B/C/D Pin Assignment Register (PBCDPAR)
Table 26-7. PBCDPAR Field Descriptions
Bits Name Description
7 PBPA Port B pin assignment. Configures the port B pins for their primary
function (D[23:16]) or digital I/O.
1 Port B pins configured for primary function (D[23:16])
0 Port B pins configured for digital I/O
6 PCDPA Ports C,D pin assignment. Configures the port C and D pins for their
primary functions (D[15:8], D[7:0]) or digital I/O.
1 Port C,D pins configured for primary function (D[15:8], D[7:0])
0 Port C,D pins configured for digital I/O
5–0 — Reserved, should be cleared.
Table 26-8. Reset Values for PBCDPAR Bits
Mode of
Operation
Port Size of
External Boot
Device
1
1
Note if the port size of the external boot device is less than the port size
of the external SDRAM, the PBCDPAR register must be written after reset
to enable the primary function(s) on ports B,C, and D, before any SDRAM
accesses are attempted.
PBPA Reset
Value
PCDPA Reset
Value
Master mode 8-bit 0 0
16-bit 1 0
32-bit 1 1
Single chip mode N/A 0 0
MCF5282 and MCF5216 ColdFire Microcontroller User’s Manual, Rev. 3