Datasheet

ATF196V8B(Q)(QL) [DATASHEET]

Atmel-0364K-PLD-ATF16V8B-8BQ-8BQL-Datasheet_072014

10. Macrocell Configuration

Software compilers support the three different OMC modes as different device types. Most compilers have the

ability to automatically select the device type, generally based on the register usage and Output Enable (OE)

usage. Register usage on the device forces the software to choose the registered mode. All combinatorial

outputs with OE controlled by the product term will force the software to choose the complex mode. The

software will choose the simple mode only when all outputs are dedicated combinatorial without OE control. The

different device types can be used to override the automatic device selection by the software. For further details,

refer to the compiler software manuals.

When using compiler software to configure the device, the user must pay special attention to the following

restrictions in each mode:

 Registered Mode

Pin 1 and pin 11 are permanently configured as clock and output enable respectively. These pins cannot

be configured as dedicated inputs in the registered mode.

 Complex Mode

Pin 1 and pin 11 become dedicated inputs and use the feedback paths of pin 19 and pin 12 respectively.

Because of this feedback path usage, pin 19 and pin 12 do not have the feedback option in this mode.

 Simple Mode

All feedback paths of the output pins are routed via the adjacent pins. In doing so, the two inner most pins

(pins 15 and 16) will not have the feedback option as these pins are always configured as dedicated

combinatorial output.

10.1 ATF16V8B(QL) Registered Mode

PAL Device Emulation/PAL Replacement. The registered mode is used if one or more registers are required.

Each macrocell can be configured as either a registered or combinatorial output or I/O, or as an input. For a

registered output or I/O, the output is enabled by the OE pin, and the register is clocked by the CLK pin. Eight

product terms are allocated to the sum term. For a combinatorial output or I/O, the output enable is controlled by

a product term, and seven product terms are allocated to the sum term. When the macrocell is configured as an

input, the output enable is permanently disabled.

Any register usage will make the compiler select this mode. The following registered devices can be emulated

using this mode:

 16R8

 16R6

 16R4

 16RP8

 16RP6

 16RP4