Register Descriptions
1246
SPRUH22I – April 2012 – Revised November 2019
Copyright © 2012–2019, Texas Instruments Incorporated
External Peripheral Interface (EPI)
Table 17-22. EPI Host-Bus 16 Configuration 2 (EPIHB16CFG2) Register Field Descriptions (continued)
Bit
Field
Value
Description
16
BURST
CS1 Burst Mode
Burst mode must be used with an ALE which is configured by programming the CSCFG and
CSCFGEXT fields in the EPIHB16CFG2 register. Burst mode must be used in ADMUX, which is set
by the MODE field in EPIHB16CFG2.
Note: Burst mode is optimized for word-length accesses.
0
Burst mode is disabled.
1
Burst mode is enabled for CS1.
15-8
Reserved
Reserved
7-6
WRWS
CS1 Write Wait States
This field adds wait states to the data phase of CS1 accesses (the address phase is not affected).
The effect is to delay the rising edge of WR (or the falling edge of WR). Each wait state encoding
adds 2 EPI clock cycles to the access time. The WRWSM bit in the EPIHB16TIME2 register can
decrease the number of wait states by 1 EPI clock cycle for greater granularity.
This field is used if the CSBAUD bit is enabled in the EPIHB16CFG2 register. This field is used in
conjunction with the EPIBAUD register and is not applicable in BURST mode.
0x0
Active WR is 2 EPI clocks
0x1
Active WR is 4 EPI clocks
0x2
Active WR is 6 EPI clocks
0x3
Active WR is 8 EPI clocks
5-4
RDWS
CS1 Read Wait States
This field adds wait states to the data phase of CS1 accesses (the address phase is not affected).
The effect is to delay the rising edge of RD/OE (or the falling edge of RD). Each wait state
encoding adds 2 EPI clock cycles to the access time. The RDWSM bit in the EPIHB16TIME2
register can decrease the number of states by 1 EPI clock cycle for greater granularity.
This field is used if the CSBAUD bit is enabled in the EPIHB16CFG2 register. This field is used in
conjunction with the EPIBAUD register and is not applicable in BURST mode.
0x0
Active RD is 2 EPI clocks
0x1
Active RD is 4 EPI clocks
0x2
Active RD is 6 EPI clocks
0x3
Active RD is 8 EPI clocks
3-2
Reserved
Reserved
1-0
MODE
CS1 Host Bus Sub-Mode
This field determines which Host Bus 16 sub-mode to use for CS1. Sub-mode use is determined by
the connected external peripheral. See
for information on how this bit field affects the
operation of the EPI signals. When used with multiple chip select option this configuration is for
CS1.
Note:
The CSBAUD bit must be set to enable this CS1 MODE field. If CSBAUD is clear, all chip-
selects use the MODE configuration defined in the EPIHB16CFG register.
0x0
ADMUX – AD[15:0]
Data and Address are muxed
0x1
ADNONMUX – D[15:0]
Data and address are separate. This mode is not practical in HB16 mode for normal peripherals
because there are generally not enough address bits available.
0x2
Continuous Read - D[15:0]
This mode is the same as ADNONMUX, but uses address switch for multiple reads instead of OE
strobing. This mode is not practical in HB16 mode for normal SRAMs because there are generally
not enough address bits available.
0x3
Reserved