Holtek HT45F5Q-3, Manual

Page: 54 / 163

Rev. 1.10 54 November 04, 2019 Rev. 1.10 55 November 04, 2019
HT45F5Q-3
Battery Charger Flash MCU
HT45F5Q-3
Battery Charger Flash MCU
Pin-shared Function Selection Registers
The limited number of supplied pins in a package can impose restrictions on the amount of functions
a certain device can contain. However by allowing the same pins to share several different functions
and providing a means of function selection, a wide range of different functions can be incorporated
into even relatively small package sizes. The device includes Port “x” Output Function Selection
register “n”, labeled as PxSn, and Input Function Selection register, labeled as IFS, which can select
the desired functions of the multi-function pin-shared pins.
The most important point to note is to make sure that the desired pin-shared function is properly
selected and also deselected. For most pin-shared functions, to select the desired pin-shared function,
the pin-shared function should first be correctly selected using the corresponding pin-shared control
register. After that the corresponding peripheral functional setting should be configured and then
the peripheral function can be enabled. However, a special point must be noted for some digital
input pins, such as INT0, CTCK, etc., which share the same pin-shared control configuration with
their corresponding general purpose I/O functions when setting the relevant pin-shared control bit
fields. To select these pin functions, in addition to the necessary pin-shared control and peripheral
functional setup aforementioned, they must also be setup as input by setting the corresponding bit
in the I/O port control register. To correctly deselect the pin-shared function, the peripheral function
should first be disabled and then the corresponding pin-shared function control register can be
modified to select other pin-shared functions.
Register
Name
Bit
7 6 5 4 3 2 1 0
PAS0 PAS07 PAS06 — — PAS03 PAS02 — —
PAS1 PAS17 PAS16 PAS15 PAS14 PAS13 PAS12 PAS11 PAS10
PBS0 PBS07 PBS06 PBS05 PBS04 PBS03 PBS02 PBS01 PBS00
PBS1 PBS17 PBS16 PBS15 PBS14 PBS13 PBS12 PBS11 PBS10
PCS0 PCS07 PCS06 PCS05 PCS04 PCS03 PCS02 PCS01 PCS00
PCS1 — — PCS15 PCS14 PCS13 PCS12 PCS11 PCS10
IFS — — — — — IFS2 IFS1 IFS0
Pin-shared Function Selection Register List
• PAS0 Register
Bit 7 6 5 4 3 2 1 0
Name PAS07 PAS06 — — PAS03 PAS02 — —
R/W R/W R/W — — R/W R/W — —
POR 0 0 — — 0 0 — —
Bit 7~6 PAS07~PAS06 : PA3 Pin-Shared function selection
00: PA3/CTCK/INT0
01: CTP
10: SDO/TX
11: PA3/CTCK/INT0
Bit 5~4 Unimplemented, read as “0”
Bit 3~2 PAS03~PAS02 : PA1 Pin-Shared function selection
00: PA1
01: OPA2P
10: PA1
11: PA1
Bit 1~0 Unimplemented, read as “0”