Sundance Spas ST201 - Manual (Page 119)

119
Sundance Technology ST201 PRELIMINARY draft 2
MINGNT
Class....................PCI Configuration Registers, Configuration
Base Address ......PCI device configuration header start
Address Offset .....0x3e
Access Mode .......Read Only
Width ...................8 bits
BIT BIT NAME BIT DESCRIPTION
7..0 MinGnt MinGnt specifies, in 250 ns increments, how long a burst period the
adapter requires when operating as a bus master. The value for
MinGnt is stored in the ConfigParm word in EEPROM. ST201-based
PCI systems return the value 10 in this field. This assumes a 33 MHz
bus (30 ns clock period), 1 clock for address phase, 10 clock latency to
first data phase, then no wait states for the 64 remaining data phases.
(1 + 10 + 64)30ns = 2.25us, rounded up to 2.5us; 2.5us/250 ns = 10