Lynx EPM-4 - Manual (Page 47)

Special Control Register
EPM-4 Reference Manual Reference – 39
Special Control Register
SCR (READ/WRITE) 00E0h
D7 D6 D5 D4 D3 D2 D1 D0
Reserved Reserved SB-SEL Reserved Reserved Reserved Reserved GPI
Table 10: Special Control Register Bit Assignments
Bit Mnemonic Description
D7-D6 — Reserved — These bits have no function.
D5 SB-SEL BIOS Selector Input — Indicates the status of jumper V4[1-2]
SB-SEL = 0 Jumper V4 [1-2] = Out (Master BIOS)
SB-SEL = 1 Jumper V4 [1-2] = In (Run Time BIOS)
Note: This general purpose bit is read-only.
D4-D1 — Reserved — These bits have no function.
D0 GPI General Purpose Input — Indicates the status of TTL input
GPI = 0 Jumper V4 [3-4] = Out
GPI = 1 Jumper V4 [3-4] = In
Note: This bit is a read-only bit.