MCF548x Reference Manual, Rev. 3
15-22 Freescale Semiconductor

15.3.2.6 FlexBus Chip Select Pin Assignment Register (PAR_FBCS)

The PAR_FBCS register controls the function of the FlexBus chip select signal pins. The PAR_FBCS

register is read/write.

12 PAR_BWE2 The PAR_BWE bit configures the BE2/BWE2 pin for its primary function or general purpose I/O.
0 BE2/BWE2 pin configured for general purpose I/O (PFBCTL6)
1 BE2/BWE2 pin configured for FlexBus BE2/BWE2 or TSIZ0 function.
The function chosen depends on the reset configuration.
11 Reserved, should be cleared. Writes have no effect and terminate without transfer error exception
10 PAR_BWE1 The PAR_BWE bit configures the BE1/BWE1 pin for its primary function or general purpose I/O.
0 BE1/BWE1 pin configured for general purpose I/O (PFBCTL5)
1 BE1/BWE1 pin configured for FlexBus BE1/BWE1 or FBADDR1 function.
The function chosen depends on the reset configuration.
9 Reserved, should be cleared.
8 PAR_BWE0 The PAR_BWE bit configures the BE0/BWE0 pin for its primary function or general purpose I/O.
0 BE0/BWE0 pin configured for general purpose I/O (PFBCTL4)
1 BE0/BWE0 pin configured for FlexBus BE0/BWE0 or FBADDR0 function.
The function chosen depends on the reset configuration.
7 Reserved, should be cleared.
6 PAR_OE The PAR_OE bit configures the OE pin for its primary function or general purpose I/O.
0OE pin configured for general purpose I/O (PFBCTL3)
1OE pin configured for Flexbus OE function.
5–4 PAR_RWB The PAR_RWB bit configures the R/W pin for its primary function or general purpose I/O
0xR/W pin configured for general purpose I/O (PFBCTL2)
10R/W pin configured for Flexbus TBST function
11R/W pin configured for Flexbus R/W function
3 Reserved, should be cleared.
2 PAR_TA The PAR_TA bit configures the TA pin for its primary function or general purpose I/O
0TA
pin configured for general purpose I/O (PFBCTL1)
1TA pin configured for Flexbus TA function
1–0 PAR_ALE The PAR_ALE bit configures the ALE pin for one of its primary functions or general purpose I/O.
0X ALE pin configured for general purpose I/O (PFBCTL0)
10 ALE pin configured for Flexbus TBST function
11 ALE pin configured for Flexbus ALE function
76543210
R 0 0 PAR_CS5 PAR_CS4 PAR_CS3 PAR_CS2 PAR_CS1 0
W
Reset00111110
Reg
Addr
MBAR + 0xA42 (PAR_FBCS)

Figure 15-23. Flexbus Chip Select Pin Assignment Register (PAR_FBCS)

Table 15-24. PAR_FBCTL Field Descriptions (Continued)

Bits Name Description