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EMDB6812

Copyright © 2004, EM Microelectronic-Marin SA

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www.emmicroelectronic.com

3.

HARDWARE CONFIGURATION

3.1 POWER-SUPPLY

EM6812 samples can be powered (VDD_IN) with two different sources :

•

Battery : VBAT

•

External Power-supply : VDD_EXT

Selection is done with a jumper configuration on CON7

Jumper CON7-3 / CON7-4

Jumper CON7-5 / CON7-6

Battery configuration

ON

OFF

External configuration

OFF

ON

VBAT :

•

Requires CR2032 3V battery in socket BT1

•

Can be measured on CON7-3

VDD_EXT :

•

Can be applied or measured on CON2-2 and CON5-2

•

When applied will light on DS9 red led

VDD_IN / IDD_IN:

•

VDD_IN is the operating power supply for the EM6812

•

IDD_IN current measurement can be done by placing ammeter between CON7-3 / CON7-4

(Battery source) or CON7-5 / CON7-6 (External source)

Notes :

1.

For In-System-programming step refer to ISP programming application note for power-

supply details. Safe operation procedure is to apply VDD_IN EM6812 from the programmer

power-supply (CON1) : No other VBAT and VDD_EXT supplied and no load on the In-

System-Programming connections.

2.

VDD_IN is connected to EM6812 VDD pin as the MAX3221 RS232 transceiver VCC (U3 +

C2 capacitor) !

3.2 VPP/TEST

During programming sequence a jumper is needed on CON7-9 / CON7-10 or CON7-11 / CON7-12.

This jumper does not need to be removed after programming.

Optionally, an external pull-down can be connected on EM6812 TEST pin (Select ON for the DIP2-

10 position 10).

3.3 PORT A SWITCHES

S1…S6 switches can be connected to EM6812 Port A

(Port A bit 0 … 5). Select ON for the

corresponding DIP1-8 position (1…6).

When the switch is activated, corresponding Port A bit is tied to ‘0’.

RS232 transceiver (TX) can be connected to Port A bit 6. Select ON for the DIP1-8 position 7.

RS232 transceiver (RX) can be connected to Port A bit 7. Select ON for the DIP1-8 position 8.