ST ST10F276E - Alternate Functions of Port6

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UM0404 Parallel ports
XSSCPORT (E880h) XBUS Reset Value: 0000h
This register is enabled and visible only when bit XPEN of SYSCON is set, and bit XSSCEN
in XPERCON is set as well. On the contrary, the standard P6, DP6 and ODP6 registers
must be used to configure pins P6.5, P6.6 and P6.7 when XSSC is disabled.
6.8.1 Alternate functions of Port6
A programmable number of chip select signals (CS4...CS0) derived from the bus control
registers (BUSCON4...BUSCON0) can be output on five pins of Port6. The other three pins
may be used for bus arbitration to accommodate additional masters in a ST10F276 system.
The number of chip select signals is selected via PORT0 during reset. The selected value
can be read from bit-field CSSEL in register RP0H (read only) in order to check the
configuration during run time.
The Table 26 summarizes the alternate functions of Port6 depending on the number of
selected chip select lines (coded via bit-field CSSEL).
Bit Function
ODP6.y
Port Open-Drain control register ODP6 bit y
’0’: Port line P6.y output driver in push-pull mode.
’1’: Port line P6.y output driver in open drain mode.
1514131211109876543210
-
XOD
P6.7
XP6
.7
XDP6
.7
XOD
P6.6
XP6
.6
XDP6
.6
XOD
P6.5
XP6
.5
XDP6
.5
RW RW RW RW RW RW RW RW RW
Bit Function
XDP6.y
Port direction register XDP6 bit y (y = 5, 6, 7 only)
‘0’: Port line P6.y is an input (high-impedance).
‘1’: Port line P6.y is an output.
XP6.y Port data register bit XP6 y (y = 5, 6, 7 only)
XODP6.y
Port Open Drain control register XODP6 bit y (y = 5, 6, 7 only)
‘0’: Port line P6.y output driver in push/pull mode.
‘1’: Port line P6.y output driver in open drain mode.