EP7212 Datasheet, PDF (59/136 Pages) Cirrus Logic – HIGH-PERFORMANCE, LOW-POWER SYSTEM-ON-CHIP WITH LCD CONTROLLER AND DIGITAL AUDIO INTERFACE(DAI)

EP7212
Bit
0:3
4
5
6
7
8
9
10
Description
Keyboard scan: This 4-bit field defines the state of the keyboard column drives. The following
table defines these states.
Keyboard Scan
0
1
2–7
8
9
10
11
12
13
14
15
Column
All driven high
All driven low
All high impedance (tristate)
Column 0 only driven high all others high impedance
Column 1 only driven high all others high impedance
Column 2 only driven high all others high impedance
Column 3 only driven high all others high impedance
Column 4 only driven high all others high impedance
Column 5 only driven high all others high impedance
Column 6 only driven high all others high impedance
Column 7 only driven high all others high impedance
TC1M: Timer counter 1 mode. Setting this bit sets TC1 to prescale mode, clearing it sets free
running mode.
TC1S: Timer counter 1 clock source. Setting this bit sets the TC1 clock source to 512 kHz, clear-
ing it sets the clock source to 2 kHz.
TC2M: Timer counter 2 mode. Setting this bit sets TC2 to prescale mode, clearing it sets free
running mode.
TC2S: Timer counter 2 clock source. Setting this bit sets the TC2 clock source to 512 kHz, clear-
ing it sets the clock source to 2 kHz.
UART1EN: Internal UART enable bit. Setting this bit enables the internal UART.
BZTOG: Bit to drive (i.e., toggle) the buzzer output directly when software mode of operation is
selected (i.e., bit BZMOD = 0). See the BZMOD and BUZFREQ (SYSCON1) bits for more
details.
BZMOD: This bit selects the buzzer drive mode. When BZMOD = 0, the buzzer drive output pin
is connected directly to the BZTOG bit. This is the software mode. When BZMOD = 1, the buzzer
drive is in the hardware mode. Two hardware sources are available to drive the pin. They are the
TC1 or a fixed internally generated clock source. The selection of which source is used to drive
the pin is determined by the state of the BUZFREQ bit in the SYSCON2 register. If the TC1 is
selected, then the buzzer output pin is connected to the TC1 under flow bit. The buzzer output
pin changes every time the timer wraps around. The frequency depends on what was pro-
grammed into the timer. See the description of the BUZFREQ and BZTOG bits (SYSCON2) for
more details.
Table 29. SYSCON1
DS474PP1
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