6

AN232R-01 Bit Bang Modes for the FT232R and FT245R

Copyright © 2006 Future Technology Devices International Ltd.

When Synchronous Bit Bang mode is enabled the IO signal lines are configured as follows:

FT232RL/

FT245RL

Pin

Number

FT232RQ/

FT245RQ

Pin

Number

Signal

Type

Description

1

30

D0

Input/Output

Bit Bang Data Bus Bit 0

5

2

D1

Input/Output

Bit Bang Data Bus Bit 1

3

32

D2

Input/Output

Bit Bang Data Bus Bit 2

11

8

D3

Input/Output

Bit Bang Data Bus Bit 3

2

31

D4

Input/Output

Bit Bang Data Bus Bit 4

9

6

D5

Input/Output

Bit Bang Data Bus Bit 5

10

7

D6

Input/Output

Bit Bang Data Bus Bit 6

6

3

D7

Input/Output

Bit Bang Data Bus Bit 7

In the case of the FT232R, any of CBUS0, CBUS1, CBUS2 or CBUS3 can be configured to bring

out the internal RD# or WR# strobes when the device is in Synchronous Bit Bang mode.

Alternatively, the CBUS pins can be used to provide clock signals by setting the appropriate values

in the EEPROM. The CBUS must be configured in the FT232R EEPROM. This option is not

available for the FT245R.

FT232RL

Pin

Number

FT232RQ

Pin

Number

Signal

Type

Description

23

22

C0

Input/Output

Configurable function

22

21

C1

Input/Output

Configurable function

13

10

C2

Input/Output

Configurable function

14

11

C3

Input/Output

Configurable function

A number of D2XX driver commands are needed to use Synchronous Bit Bang mode. The

commands of interest are listed below: