Every IP contains an IP PROM, whose size is at least 32 x 8 bits. The ID PROM aids in software auto configuration and configuration management. The user's software, or a supplied driver, may verify that the device it expects is actually installed at the location it expects, and is nominally functional. The ID PROM contains the manufacturing recision level of the IP. If a driver requires that a particular revision be present, it may check it directly.
Standard data in the ID PROM on the IP-Octal Serial is shown in Figure 8 below. For more information on IP ID PROMs refer to the IndustryPack Logic Interface Specification, available from GreenSpring Computers.
The location of the ID PROM in the host's address space is dependent on which carrier is used. Normally for VMEbus carriers the ID PROM space is directly above the IP's I/O space, or at IP-base + $80. macintosh drivers use the ID PROM automatically. RM1260 address may be derived from Figure 8 below by multiplying the addresses given by two, then subtracting one. RM1270 addresses may be derived by multiplying the addresses given my two, then adding one.
The ID PROM used is an AMD 27LS19A.
| 3F
19 |
(available for user) |
| 17 | CRC |
| 15 | No of bytes used (0B) |
| 13 | Driver ID, high byte |
| 11 | Driver ID, low byte |
| 0F | reserved (00) |
| 0D | Revision (A1) |
| 0B | Model No IP-Octal Serial (22) |
| 09 | Manufacturer ID GreenSpring (F0) |
| 07 | ASCII "C" (43) |
| 05 | ASCII "A" (41) |
| 03 | ASCII "P" (50) |
| 01 | ASCII "I" (49) |
Figure 8 ID PROM Data (hex)