| |||
Home > Programmers Model > Register descriptions > Maximum Number of Outstanding Transactions Register |
The max_ot Register characteristics are:
This register enables you to program the maximum number of address requests for the AR and AW channels. See Outstanding transaction regulation for more information.
The outstanding transaction limits have an integer part and a fractional part as follows:
Corresponds to the integer part of the maximum outstanding AR addresses.
Corresponds to the integer part of the maximum outstanding AW addresses.
Corresponds to the fractional part of the maximum outstanding AR addresses.
Corresponds to the fractional part of the maximum outstanding AW addresses.
A value of 0 for both the integer and fractional parts disables the programmable regulation so that the NIC-400 base product configuration limits apply.
The AW and AR outstanding transaction limits are enabled when you set the corresponding en_aw_ot or en_ar_ot control bits of the QoS control register. See QoS Control Register and Table 3.2.
You cannot increase the limits above either:
the configuration limits you set at design time
the CoreLink NIC-400 Network Interconnect limit of 32.
Only available when you select outstanding transaction regulation in AMBA Designer.
See Table 3.1.
Figure 3.2 shows the bit assignments.
Table 3.3 shows the bit assignments.
Table 3.3. max_ot Register bit assignments
Bits | Name | Function |
---|---|---|
[31:30] | - | Reserved. Do not modify. Read as zero. |
[29:24] | ar_max_oti | Integer part of the maximum outstanding AR addresses. |
[23:16] | ar_max_otf | Fractional part of the maximum outstanding AR addresses. |
[15:14] | - | Reserved. Do not modify. Read as zero. |
[13:8] | aw_max_oti | Integer part of the maximum outstanding AW addresses. |
[7:0] | aw_max_otf | Fractional part of the maximum outstanding AW addresses. |