TTP/C-C1 Communications Controller Data Sheet

AS8201

Rev. NC, October 1999

Page 10 of 13

Austria Mikro Systeme International AG

Integrated Power-On Reset

An internal Power-On Reset generator is integrated. When The supply voltage ramps up, the

internal reset signal is kept active (low) for about 24 us typical. To activate this function the

RESETB must be left unconnected.

Parameter

Symbol

Min

Typ

Max

Unit

supply voltage slope

dV/dt

250

-

-

kV/s

power on reset active time after VDD >

1,2V

16

24

34

us

external reset low to internal high

81

118

173

ns

external reset high to internal low

130

129

104

ns

Oscillator circuitry

The internal oscillator cell requires an external quartz or an external oscillator respectively

(Figure 5, Figure 6). The internal controller clock is available at the port MICROTICK (inverted

to clock signal applied at XOUT0).

TTA-C1

XIN0

XOUT0

XENA0

VSS

XIN1

XOUT1

XENA1

VSS

20Mhz

16Mhz

TTA-C1

XIN0

XOUT0

XENA0

VSS

XIN1

XOUT1

XENA1

VSS

20Mhz

OSC

16Mhz

OSC

XENA0

XOUT0

XIN0

XENA1

XOUT1

XIN1

Figure 5: Quartz Circuit

Figure 6: Oscillator Circuit

TTP/C Bus Interface

Pin Name

mode

width

comment

CTS

out

2

transmitter clear to send

OE

in

2

transmitter output enable

TXD

out

2

transmit data

RXD

in

2

receiver input

BDE

out

2

bus driver enable

Table 5: TTP/C Bus Interface Ports

The controller can be connected to transceivers with recessive state and to transceivers with

three-state outputs, respectively. For safe operation of the device the bus driver enable signal

BDE must be connected with output enable OE. To deactivate the bus guardian the OE signal

has to be tied to VCC. Applications with recessive state transceivers do not use the CTS

signal.