Module unsigned 

This is an implementation of unsigned types of various bit widths which accompanies the signed one’s-complement types. Since these types are unsigned, there is no sign bit and they aren’t really one’s-complement types. But the interface to these is mostly similar to that of the signed (real one’s-complement) types.

Macros

from_native_type_to_self 🔒

This macro implements conversions from native types to Unsigned*Bit which are always possible (e.g. From<u8> for Unsigned9Bit).

from_self_to_native_type 🔒

This macro implements conversions from Unsigned*Bit to native types which are always possible (e.g. From<Unsigned9Bit> for i16).

try_from_native_type_to_self 🔒

This macro implements a conversions from native types to Unsigned*Bit where the conversion may not always fit. For example TryFrom<u64> for Unsigned36Bit.

try_from_self_to_native_type 🔒

This macro implements conversions from Unsigned*Bit to native types where the conversion may not always fit. For example TryFrom<Unsigned18Bit> for u8.

unsigned_ones_complement_impl 🔒

This macro implements the base functionality of the unsigned types. The SelfT argument is the name of the (unsigned in this case) type we are defining. BITS is the bit width of the type we are defining. InnerT is the name of the native type which will store those bits. SignedPeerT is the name of the equivalent signed type having the same width (e.g. for Unsigned18Bit this should be Signed18Bit).

Structs

Unsigned5Bit

Unsigned5Bit is used as a system configuration value; that is, an index into F-memory.

Unsigned6Bit

Unsigned6Bit is used as an X-register address. That is, the j in Xj.

Unsigned9Bit

Unsigned9Bit is the value of a “quarter” of the 36-bit TX-2 machine word. A number of instructions - and in particular the Exchange Unit - work on the quarters of a word.

Unsigned12Bit

Unsigned12Bit is used as the mode of a connected I/O device.

Unsigned18Bit

Unsigned18Bit is the value of a “half” of the 36-bit TX-2 machine word. We use this type to hold STUV-memory addresses, among other things. Physical memory addresses though are only 17 bits wide. The remaining bit can be used to “mark” an address either for tracing (when it’s an instruction address) or for deferred addressing (when it’s an operand address).

Unsigned36Bit

Unsigned36Bit is the basic machine word of the TX-2. This is the width of the registers in the Arithmetic Unit, and it is the unit on which the Exchange Unit operates when performing memory fetches or stores. This is also the width of all instructions.