The block diagram of ALU and its communication with other blocks of the car are shown in drawing the registers Rg1 – Rg7 in whom information arriving from random access or passive memory of N1, N2 is processed are a part of ALU.. NS; the logical schemes realizing processing of words on the microteams arriving from a control unit.
Bezznakovy binary numbers can accept only positive values and therefore have almost twice the bigger range, than sign numbers of the same length. Younger words of numbers with the increased accuracy are used as bezznakovy numbers.
The choice of primary or secondary set of registers is controlled by bit 0 in the register of the mode and the status of the processor (MSTAT). If this bit zero, is used primary set if it unit, is used a secondary set of registers.
The entrance port Y can also accept data from two sources: from a set of the registers AY or from the register of feedback of AF. The block of the registers AY consists of two registers AY0 and AY These registers are read and can be written down via the tire DMD, and also can be written down via the tire PMD. The exit of the block of the registers AY coincides by the opportunities with the block of registers AH.
The logic of a flag of transfer is based on bezznakovy arithmetics. This flag is set in case transfer from the senior category of number which cannot be written down in result is generated. This flag is very useful at operations with verbose representations of numbers to younger words.
Division with an unary accuracy, with a 32-bit dividend and a 16-bit divider, giving 16-bit private, is carried out for 16 cycles. Also can be calculated private smaller and bigger word length. The divider can contain in AX0, AX1 or any of R registers. The senior part of a sign dividend can contain in AY1 or AF. The senior part of a bezznakovy dividend can contain only in AF. The younger part of a dividend has to be in AY After completion of operation of division private is in AY
Some changes of a format have to be used to guarantee correctness of the private. For example, if both operands sign and completely fractional (a dividend in a format 31 and a divider in a format 1, result completely fractional (in a format 1 and therefore the dividend has to be less divider for receiving right result.